diff --git a/accessible/tests/Makefile.in b/accessible/tests/Makefile.in
index b602f735b2f..4dd93c243e6 100644
--- a/accessible/tests/Makefile.in
+++ b/accessible/tests/Makefile.in
@@ -45,7 +45,7 @@ include $(DEPTH)/config/autoconf.mk
 
 MODULE	= test_accessibility
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= mochitest
 endif
 
diff --git a/browser/base/Makefile.in b/browser/base/Makefile.in
index 5ebe6cc9ac1..d53f83a73e2 100644
--- a/browser/base/Makefile.in
+++ b/browser/base/Makefile.in
@@ -48,7 +48,7 @@ abs_srcdir = $(shell cd $(srcdir) && pwd)
 
 CHROME_DEPS += $(abs_srcdir)/content/overrides/app-license.html
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS += content/test
 endif
 
diff --git a/browser/components/feeds/Makefile.in b/browser/components/feeds/Makefile.in
index f1c4c9825fc..93681d67f15 100644
--- a/browser/components/feeds/Makefile.in
+++ b/browser/components/feeds/Makefile.in
@@ -43,7 +43,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS = public src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS += test
 endif
 
diff --git a/browser/components/places/tests/Makefile.in b/browser/components/places/tests/Makefile.in
index 9a43c7c4e43..31500f85c25 100644
--- a/browser/components/places/tests/Makefile.in
+++ b/browser/components/places/tests/Makefile.in
@@ -47,9 +47,6 @@ MODULE		= test_browser_places
 
 XPCSHELL_TESTS = unit
 
-ifdef MOZ_MOCHITEST
-	DIRS += browser
-	DIRS += perf
-endif
+DIRS = browser perf
 
 include $(topsrcdir)/config/rules.mk
diff --git a/browser/components/preferences/Makefile.in b/browser/components/preferences/Makefile.in
index 056b3b49abb..1a2f667bd63 100644
--- a/browser/components/preferences/Makefile.in
+++ b/browser/components/preferences/Makefile.in
@@ -43,7 +43,7 @@ VPATH		= @srcdir@
 
 include $(DEPTH)/config/autoconf.mk
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS += tests
 endif
 
diff --git a/browser/components/safebrowsing/Makefile.in b/browser/components/safebrowsing/Makefile.in
index 8e763cd28e7..98762cd69df 100644
--- a/browser/components/safebrowsing/Makefile.in
+++ b/browser/components/safebrowsing/Makefile.in
@@ -45,7 +45,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS      = src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS += content/test
 endif
 
diff --git a/browser/components/search/Makefile.in b/browser/components/search/Makefile.in
index 9d14bbd85c2..cca70b4d2b5 100644
--- a/browser/components/search/Makefile.in
+++ b/browser/components/search/Makefile.in
@@ -43,7 +43,7 @@ VPATH     = @srcdir@
 
 include $(DEPTH)/config/autoconf.mk
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS = test
 endif
 
diff --git a/browser/components/sessionstore/Makefile.in b/browser/components/sessionstore/Makefile.in
index 754426761bc..81468ad0d42 100644
--- a/browser/components/sessionstore/Makefile.in
+++ b/browser/components/sessionstore/Makefile.in
@@ -50,7 +50,7 @@ XPIDLSRCS = \
 
 DIRS = src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS += test
 endif
 
diff --git a/browser/components/shell/Makefile.in b/browser/components/shell/Makefile.in
index ae69168d65e..7f3883694b0 100644
--- a/browser/components/shell/Makefile.in
+++ b/browser/components/shell/Makefile.in
@@ -44,7 +44,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS = public src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS += test
 endif
 
diff --git a/browser/fuel/Makefile.in b/browser/fuel/Makefile.in
index 02d59d4632a..5d326fc78d0 100644
--- a/browser/fuel/Makefile.in
+++ b/browser/fuel/Makefile.in
@@ -44,7 +44,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS = public src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS += test
 endif
 
diff --git a/config/autoconf.mk.in b/config/autoconf.mk.in
index b001cc3fa48..f99a63c16d4 100644
--- a/config/autoconf.mk.in
+++ b/config/autoconf.mk.in
@@ -161,7 +161,6 @@ MOZ_OGG = @MOZ_OGG@
 MOZ_MEDIA = @MOZ_MEDIA@
 NS_PRINTING = @NS_PRINTING@
 MOZ_CRASHREPORTER = @MOZ_CRASHREPORTER@
-MOZ_MOCHITEST = @MOZ_MOCHITEST@
 MOZ_HELP_VIEWER = @MOZ_HELP_VIEWER@
 MOC= @MOC@
 
diff --git a/configure.in b/configure.in
index 93f1114412f..8f549882589 100644
--- a/configure.in
+++ b/configure.in
@@ -4357,7 +4357,6 @@ MOZ_JSLOADER=1
 MOZ_LIBART_CFLAGS=
 MOZ_LIBART_LIBS=
 MOZ_MATHML=1
-MOZ_MOCHITEST=1
 MOZ_MORK=1
 MOZ_MORKREADER=
 MOZ_AUTH_EXTENSION=1
@@ -5529,15 +5528,6 @@ if test -z "$MOZ_CRASHREPORTER_ENABLE_PERCENT"; then
 fi
 AC_DEFINE_UNQUOTED(MOZ_CRASHREPORTER_ENABLE_PERCENT, $MOZ_CRASHREPORTER_ENABLE_PERCENT)
 
-
-dnl ========================================================
-dnl = Build mochitest JS/DOM tests (on by default)
-dnl ========================================================
-MOZ_ARG_DISABLE_BOOL(mochitest,
-[  --disable-mochitest        Disable mochitest harness],
-    MOZ_MOCHITEST=,
-    MOZ_MOCHITEST=1 )
-
 dnl ========================================================
 dnl = Enable compilation of specific extension modules
 dnl ========================================================
@@ -7915,7 +7905,6 @@ AC_SUBST(MOZ_SPELLCHECK)
 AC_SUBST(MOZ_XPFE_COMPONENTS)
 AC_SUBST(MOZ_USER_DIR)
 AC_SUBST(MOZ_CRASHREPORTER)
-AC_SUBST(MOZ_MOCHITEST)
 
 AC_SUBST(ENABLE_STRIP)
 AC_SUBST(PKG_SKIP_STRIP)
diff --git a/content/canvas/Makefile.in b/content/canvas/Makefile.in
index cd71f556bdb..93db91538ad 100644
--- a/content/canvas/Makefile.in
+++ b/content/canvas/Makefile.in
@@ -45,7 +45,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS		= public src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/content/events/Makefile.in b/content/events/Makefile.in
index 73d3c2dde52..ce4c9498156 100644
--- a/content/events/Makefile.in
+++ b/content/events/Makefile.in
@@ -44,7 +44,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS		= public src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/content/html/content/Makefile.in b/content/html/content/Makefile.in
index 99d2ec7d635..51ee41017e9 100644
--- a/content/html/content/Makefile.in
+++ b/content/html/content/Makefile.in
@@ -44,7 +44,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS		= public src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/content/html/document/Makefile.in b/content/html/document/Makefile.in
index 99d2ec7d635..51ee41017e9 100644
--- a/content/html/document/Makefile.in
+++ b/content/html/document/Makefile.in
@@ -44,7 +44,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS		= public src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/content/media/video/Makefile.in b/content/media/video/Makefile.in
index 14155e2b0e3..d07f2ecca24 100644
--- a/content/media/video/Makefile.in
+++ b/content/media/video/Makefile.in
@@ -46,7 +46,7 @@ DIRS		= \
 		src \
 		$(NULL)
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS            += test
 endif
 
diff --git a/content/svg/content/Makefile.in b/content/svg/content/Makefile.in
index d90c200d593..6a5fa5d8d87 100644
--- a/content/svg/content/Makefile.in
+++ b/content/svg/content/Makefile.in
@@ -45,7 +45,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS		= src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS += test
 endif
 
diff --git a/content/xbl/Makefile.in b/content/xbl/Makefile.in
index 6bb8f65be16..8b645c2f011 100644
--- a/content/xbl/Makefile.in
+++ b/content/xbl/Makefile.in
@@ -44,7 +44,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS		= public src builtin
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/content/xml/document/Makefile.in b/content/xml/document/Makefile.in
index 9d6f7732400..2d99a9c59f6 100644
--- a/content/xml/document/Makefile.in
+++ b/content/xml/document/Makefile.in
@@ -44,7 +44,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS		= public resources src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS            += test
 endif
 
diff --git a/content/xslt/Makefile.in b/content/xslt/Makefile.in
index 08d9a2309e7..d52ae8f4eb1 100755
--- a/content/xslt/Makefile.in
+++ b/content/xslt/Makefile.in
@@ -45,11 +45,8 @@ include $(DEPTH)/config/autoconf.mk
 DIRS = public src
 
 ifdef ENABLE_TESTS
-DIRS += tests/buster
-endif
-
-ifdef MOZ_MOCHITEST
-DIRS += tests/mochitest
+DIRS += tests/buster \
+	tests/mochitest
 endif
 
 include $(topsrcdir)/config/rules.mk
diff --git a/content/xul/document/Makefile.in b/content/xul/document/Makefile.in
index ee57a1ac69d..8aefcf986b1 100644
--- a/content/xul/document/Makefile.in
+++ b/content/xul/document/Makefile.in
@@ -45,7 +45,7 @@ include $(DEPTH)/config/autoconf.mk
 MODULE		= xuldoc
 DIRS		= public src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/docshell/Makefile.in b/docshell/Makefile.in
index bb1de6887e8..ff74e0d1f7d 100644
--- a/docshell/Makefile.in
+++ b/docshell/Makefile.in
@@ -51,7 +51,7 @@ DIRS = \
 	resources \
 	$(NULL)
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/dom/src/jsurl/Makefile.in b/dom/src/jsurl/Makefile.in
index 9f48f3ebf19..1732a89560e 100644
--- a/dom/src/jsurl/Makefile.in
+++ b/dom/src/jsurl/Makefile.in
@@ -87,7 +87,7 @@ DEFINES		+= -DDEBUG_GC
 endif
 
 DIRS            = $(NULL)
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS            += test
 endif
 
diff --git a/dom/src/threads/Makefile.in b/dom/src/threads/Makefile.in
index 8b741c2b07a..cae2810bc97 100644
--- a/dom/src/threads/Makefile.in
+++ b/dom/src/threads/Makefile.in
@@ -75,7 +75,7 @@ LOCAL_INCLUDES = \
   -I$(topsrcdir)/dom/src/base \
   $(NULL)
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS += test
 endif
 
diff --git a/dom/tests/Makefile.in b/dom/tests/Makefile.in
index f09f4878d2d..91f57083567 100644
--- a/dom/tests/Makefile.in
+++ b/dom/tests/Makefile.in
@@ -44,11 +44,8 @@ include $(DEPTH)/config/autoconf.mk
 
 MODULE = test_dom
 
-ifdef MOZ_MOCHITEST
-DIRS		+= mochitest
-endif
-
 ifdef ENABLE_TESTS
+DIRS		+= mochitest
 XPCSHELL_TESTS = unit
 endif
 
diff --git a/editor/composer/Makefile.in b/editor/composer/Makefile.in
index 2b3fa3067b6..0aadbca1b9c 100644
--- a/editor/composer/Makefile.in
+++ b/editor/composer/Makefile.in
@@ -48,7 +48,7 @@ ifndef MOZ_PLAINTEXT_EDITOR_ONLY
 DIRS		+= src
 endif
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/embedding/Makefile.in b/embedding/Makefile.in
index 9e88839660a..3b636020333 100644
--- a/embedding/Makefile.in
+++ b/embedding/Makefile.in
@@ -50,9 +50,6 @@ DIRS = base components browser
 
 ifdef ENABLE_TESTS
 XPCSHELL_TESTS = tests/unit
-endif
-
-ifdef MOZ_MOCHITEST
 DIRS += test
 endif
 
diff --git a/extensions/universalchardet/tests/Makefile.in b/extensions/universalchardet/tests/Makefile.in
index 3f8daea8b37..e900286a4ab 100644
--- a/extensions/universalchardet/tests/Makefile.in
+++ b/extensions/universalchardet/tests/Makefile.in
@@ -67,7 +67,6 @@ LIBS		+= \
 
 include $(topsrcdir)/config/rules.mk
 
-ifdef MOZ_MOCHITEST
 relativesrcdir = extensions/universalchardet/tests
 
 _TEST_FILES =	\
@@ -88,5 +87,3 @@ _TEST_FILES =	\
 
 libs:: $(_TEST_FILES)
 	$(INSTALL) $(foreach f,$^,"$f") $(DEPTH)/_tests/testing/mochitest/tests/$(relativesrcdir)
-
-endif # MOZ_MOCHITEST
diff --git a/intl/uconv/tests/Makefile.in b/intl/uconv/tests/Makefile.in
index 58f718c3fca..b08411db409 100644
--- a/intl/uconv/tests/Makefile.in
+++ b/intl/uconv/tests/Makefile.in
@@ -69,7 +69,6 @@ SIMPLE_PROGRAMS	= $(CPPSRCS:.cpp=$(BIN_SUFFIX))
 
 endif # MOZ_ENABLE_LIBXUL
 
-ifdef MOZ_MOCHITEST
 relativesrcdir	= intl/uconv/tests
 
 _TEST_FILES =	\
@@ -78,8 +77,6 @@ _TEST_FILES =	\
 libs:: $(_TEST_FILES)
 	$(INSTALL) $(foreach f,$^,"$f") $(DEPTH)/_tests/testing/mochitest/tests/$(relativesrcdir)
 
-endif # MOZ_MOCHITEST
-
 include $(topsrcdir)/config/rules.mk
 
 ifndef MOZ_ENABLE_LIBXUL
diff --git a/js/src/xpconnect/tests/Makefile.in b/js/src/xpconnect/tests/Makefile.in
index 8b017cc9eed..66289bda210 100644
--- a/js/src/xpconnect/tests/Makefile.in
+++ b/js/src/xpconnect/tests/Makefile.in
@@ -53,20 +53,13 @@ REQUIRES	= xpconnect \
 		  xpconnect_tests \
 		  $(NULL)
 
-DIRS		= idl
+DIRS		= idl mochitest
 
 ifndef MOZ_ENABLE_LIBXUL
 DIRS += components
 endif
 
-ifdef MOZ_MOCHITEST
-DIRS += mochitest \
-	$(NULL)
-endif
-
-ifdef ENABLE_TESTS
 XPCSHELL_TESTS = unit
-endif
 
 CPPSRCS		= TestXPC.cpp
 
diff --git a/layout/base/Makefile.in b/layout/base/Makefile.in
index 669aaa1d14f..4c90a9d68c6 100644
--- a/layout/base/Makefile.in
+++ b/layout/base/Makefile.in
@@ -42,7 +42,7 @@ VPATH		= @srcdir@
 
 include $(DEPTH)/config/autoconf.mk
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= tests
 endif
 
diff --git a/layout/base/tests/Makefile.in b/layout/base/tests/Makefile.in
index 3a86196949f..703486e43c3 100644
--- a/layout/base/tests/Makefile.in
+++ b/layout/base/tests/Makefile.in
@@ -78,8 +78,6 @@ include $(topsrcdir)/config/rules.mk
 
 DEFINES += -D_IMPL_NS_LAYOUT
 
-ifdef MOZ_MOCHITEST
-
 _TEST_FILES =	\
 		test_bug66619.html \
 		test_bug386575.xhtml \
@@ -101,5 +99,3 @@ _TEST_FILES =	\
 
 libs:: $(_TEST_FILES)
 	$(INSTALL) $(foreach f,$^,"$f") $(DEPTH)/_tests/testing/mochitest/tests/$(relativesrcdir)
-
-endif # MOZ_MOCHITEST
diff --git a/layout/forms/Makefile.in b/layout/forms/Makefile.in
index ad9af9933a0..b4ad88dca8f 100644
--- a/layout/forms/Makefile.in
+++ b/layout/forms/Makefile.in
@@ -44,7 +44,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS = $(NULL)
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/layout/generic/Makefile.in b/layout/generic/Makefile.in
index bcaec3a55fd..e9bfdea9f1e 100644
--- a/layout/generic/Makefile.in
+++ b/layout/generic/Makefile.in
@@ -41,7 +41,7 @@ VPATH		= @srcdir@
 
 include $(DEPTH)/config/autoconf.mk
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/layout/style/Makefile.in b/layout/style/Makefile.in
index 867b421e68a..00f6f8f41d4 100644
--- a/layout/style/Makefile.in
+++ b/layout/style/Makefile.in
@@ -43,7 +43,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS = xbl-marquee
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/layout/tables/Makefile.in b/layout/tables/Makefile.in
index 5efb1d02ee5..58a35b4eec6 100644
--- a/layout/tables/Makefile.in
+++ b/layout/tables/Makefile.in
@@ -89,7 +89,7 @@ CPPSRCS		= \
 # we don't want the shared lib, but we want to force the creation of a static lib.
 FORCE_STATIC_LIB = 1
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS  = test
 endif
 
diff --git a/layout/xul/Makefile.in b/layout/xul/Makefile.in
index 36f7cfee7d5..d1c8794c0d1 100644
--- a/layout/xul/Makefile.in
+++ b/layout/xul/Makefile.in
@@ -44,7 +44,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS		= base
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/layout/xul/base/Makefile.in b/layout/xul/base/Makefile.in
index 99d2ec7d635..51ee41017e9 100644
--- a/layout/xul/base/Makefile.in
+++ b/layout/xul/base/Makefile.in
@@ -44,7 +44,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS		= public src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS		+= test
 endif
 
diff --git a/modules/libjar/test/Makefile.in b/modules/libjar/test/Makefile.in
index 5d8d391554d..2eaee5a4a7d 100644
--- a/modules/libjar/test/Makefile.in
+++ b/modules/libjar/test/Makefile.in
@@ -47,8 +47,6 @@ MODULE		= test_libjar
 
 XPCSHELL_TESTS = unit
 
-ifdef MOZ_MOCHITEST
-DIRS		+= mochitest
-endif
+DIRS		= mochitest
 
 include $(topsrcdir)/config/rules.mk
diff --git a/modules/libpr0n/test/Makefile.in b/modules/libpr0n/test/Makefile.in
index 8efbb592111..562f3705768 100644
--- a/modules/libpr0n/test/Makefile.in
+++ b/modules/libpr0n/test/Makefile.in
@@ -48,9 +48,7 @@ MODULE		= test_libpr0n
 
 XPCSHELL_TESTS  = unit
 
-#ifdef MOZ_MOCHITEST
 DIRS            += mochitest
-#endif
 
 include $(topsrcdir)/config/rules.mk
 
diff --git a/parser/htmlparser/tests/Makefile.in b/parser/htmlparser/tests/Makefile.in
index 8233a4032a6..2294a11300e 100644
--- a/parser/htmlparser/tests/Makefile.in
+++ b/parser/htmlparser/tests/Makefile.in
@@ -45,6 +45,7 @@ include $(DEPTH)/config/autoconf.mk
 DIRS = \
 	grabpage \
 	html \
+	mochitest \
 	$(NULL)
 
 ifndef MOZ_ENABLE_LIBXUL
@@ -53,9 +54,4 @@ DIRS += \
 	$(NULL)
 endif
 
-ifdef MOZ_MOCHITEST
-DIRS += mochitest \
-        $(NULL)
-endif
-
 include $(topsrcdir)/config/rules.mk
diff --git a/testing/mochitest/Makefile.in b/testing/mochitest/Makefile.in
index 50bedabbfde..47946da67b7 100644
--- a/testing/mochitest/Makefile.in
+++ b/testing/mochitest/Makefile.in
@@ -133,8 +133,5 @@ GARBAGE += runtests.py automation.py
 libs:: $(_SERV_FILES)
 	$(INSTALL) $^ $(_DEST_DIR)
 
-#XXX: need to fix bug 447642
-ifdef ENABLE_TESTS
 libs::
 	$(PYTHON) $(DEPTH)/_profile/pgo/genpgocert.py --gen-server
-endif
\ No newline at end of file
diff --git a/toolkit/components/microformats/Makefile.in b/toolkit/components/microformats/Makefile.in
index d466ea86f4a..ae92b6dbfa2 100644
--- a/toolkit/components/microformats/Makefile.in
+++ b/toolkit/components/microformats/Makefile.in
@@ -43,7 +43,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS = src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS += tests
 endif
 
diff --git a/toolkit/components/places/tests/Makefile.in b/toolkit/components/places/tests/Makefile.in
index 690b09ec603..97a2dc108f2 100644
--- a/toolkit/components/places/tests/Makefile.in
+++ b/toolkit/components/places/tests/Makefile.in
@@ -62,14 +62,12 @@ MOCHI_TESTS = mochitest/test_bug_405924.html \
 MOCHI_CONTENT = mochitest/prompt_common.js \
 								$(NULL)
 
-ifdef MOZ_MOCHITEST
 DIRS = \
 	chrome \
 	mochitest/bug_411966 \
 # These tests are disabled for the time being, see bug 416066
 #	browser \
 	$(NULL)
-endif
 
 include $(topsrcdir)/config/rules.mk
 
diff --git a/toolkit/content/tests/Makefile.in b/toolkit/content/tests/Makefile.in
index 5640c12e1da..5bbab5890a1 100644
--- a/toolkit/content/tests/Makefile.in
+++ b/toolkit/content/tests/Makefile.in
@@ -47,8 +47,6 @@ MODULE		= test_toolkit_general
 
 XPCSHELL_TESTS = unit
 
-ifdef MOZ_MOCHITEST
 DIRS = chrome widgets
-endif
 
 include $(topsrcdir)/config/rules.mk
diff --git a/toolkit/themes/pinstripe/Makefile.in b/toolkit/themes/pinstripe/Makefile.in
index d8124bbcc63..ed5927cf356 100644
--- a/toolkit/themes/pinstripe/Makefile.in
+++ b/toolkit/themes/pinstripe/Makefile.in
@@ -48,7 +48,7 @@ ifdef MOZ_HELP_VIEWER
 DIRS	+= help
 endif
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS  += tests
 endif
 
diff --git a/toolkit/toolkit-tiers.mk b/toolkit/toolkit-tiers.mk
index 6f4c1606292..be0d784a7e3 100644
--- a/toolkit/toolkit-tiers.mk
+++ b/toolkit/toolkit-tiers.mk
@@ -268,6 +268,6 @@ ifdef MOZ_MAPINFO
 tier_toolkit_dirs	+= tools/codesighs
 endif
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 tier_toolkit_dirs	+= testing/mochitest
 endif
diff --git a/widget/Makefile.in b/widget/Makefile.in
index 3488e317753..f495accb88e 100644
--- a/widget/Makefile.in
+++ b/widget/Makefile.in
@@ -44,7 +44,7 @@ include $(DEPTH)/config/autoconf.mk
 
 DIRS	= public src
 
-ifdef MOZ_MOCHITEST
+ifdef ENABLE_TESTS
 DIRS  += tests
 endif