diff --git a/bind/gengo.go b/bind/gengo.go
index 1b8ac3c..f4467fe 100644
--- a/bind/gengo.go
+++ b/bind/gengo.go
@@ -24,6 +24,7 @@ func (g *goGen) errorf(format string, args ...interface{}) {
 }
 
 const goPreamble = `// Package go_%s is an autogenerated binder stub for package %s.
+//   gobind -lang=go %s
 //
 // File is generated by gobind. Do not edit.
 package go_%s
@@ -37,7 +38,7 @@ import (
 
 func (g *goGen) genPreamble() {
 	n := g.pkg.Name()
-	g.Printf(goPreamble, n, n, n, g.pkg.Path())
+	g.Printf(goPreamble, n, n, g.pkg.Path(), n, g.pkg.Path())
 }
 
 func (g *goGen) genFuncBody(o *types.Func, selectorLHS string) {
diff --git a/bind/genjava.go b/bind/genjava.go
index 23238e9..6e462cd 100644
--- a/bind/genjava.go
+++ b/bind/genjava.go
@@ -478,6 +478,7 @@ func (g *javaGen) errorf(format string, args ...interface{}) {
 }
 
 const javaPreamble = `// Java Package %s is a proxy for talking to a Go program.
+//   gobind -lang=java %s
 //
 // File is generated by gobind. Do not edit.
 package go.%s;
@@ -487,7 +488,7 @@ import go.Seq;
 `
 
 func (g *javaGen) gen() error {
-	g.Printf(javaPreamble, g.pkg.Name(), g.pkg.Name())
+	g.Printf(javaPreamble, g.pkg.Name(), g.pkg.Path(), g.pkg.Name())
 
 	firstRune, size := utf8.DecodeRuneInString(g.pkg.Name())
 	className := string(unicode.ToUpper(firstRune)) + g.pkg.Name()[size:]
diff --git a/bind/java/testpkg/Testpkg.java b/bind/java/testpkg/Testpkg.java
index e50f800..0435faa 100644
--- a/bind/java/testpkg/Testpkg.java
+++ b/bind/java/testpkg/Testpkg.java
@@ -1,13 +1,15 @@
 // Java Package testpkg is a proxy for talking to a Go program.
+//   gobind -lang=java code.google.com/p/go.mobile/bind/java/testpkg
 //
 // File is generated by gobind. Do not edit.
-// Or do, I'm a comment, not a cop.
 package go.testpkg;
 
 import go.Seq;
 
-public final class Testpkg {
-    public long Add(long x, long y) {
+public abstract class Testpkg {
+    private Testpkg() {} // uninstantiable
+    
+    public static long Add(long x, long y) {
         go.Seq _in = new go.Seq();
         go.Seq _out = new go.Seq();
         long _result;
@@ -18,14 +20,14 @@ public final class Testpkg {
         return _result;
     }
     
-    public void Call(I i) {
+    public static void Call(I i) {
         go.Seq _in = new go.Seq();
         go.Seq _out = new go.Seq();
         _in.writeRef(i.ref());
         Seq.send(DESCRIPTOR, CALL_Call, _in, _out);
     }
     
-    public void GC() {
+    public static void GC() {
         go.Seq _in = new go.Seq();
         go.Seq _out = new go.Seq();
         Seq.send(DESCRIPTOR, CALL_GC, _in, _out);
@@ -47,7 +49,6 @@ public final class Testpkg {
             public void call(int code, go.Seq in, go.Seq out) {
                 switch (code) {
                 case Proxy.CALL_F: {
-                    // TODO(crawshaw): handle catching a Exception
                     this.F();
                     return;
                 }
@@ -73,21 +74,22 @@ public final class Testpkg {
             public void F() {
                 go.Seq _in = new go.Seq();
                 go.Seq _out = new go.Seq();
+                _in.writeRef(ref);
                 Seq.send(DESCRIPTOR, CALL_F, _in, _out);
             }
             
-            static final int CALL_F = 0x0a01;
+            static final int CALL_F = 0x10a;
         }
     }
     
-    public void Keep(I i) {
+    public static void Keep(I i) {
         go.Seq _in = new go.Seq();
         go.Seq _out = new go.Seq();
         _in.writeRef(i.ref());
         Seq.send(DESCRIPTOR, CALL_Keep, _in, _out);
     }
     
-    public S New() {
+    public static S New() {
         go.Seq _in = new go.Seq();
         go.Seq _out = new go.Seq();
         S _result;
@@ -96,7 +98,7 @@ public final class Testpkg {
         return _result;
     }
     
-    public long NumSCollected() {
+    public static long NumSCollected() {
         go.Seq _in = new go.Seq();
         go.Seq _out = new go.Seq();
         long _result;
@@ -107,7 +109,7 @@ public final class Testpkg {
     
     public static final class S implements go.Seq.Object {
         private static final String DESCRIPTOR = "go.testpkg.S";
-        private static final int CALL_F = 0x0c00;
+        private static final int CALL_F = 0x00c;
         
         private go.Seq.Ref ref;
         
@@ -116,7 +118,7 @@ public final class Testpkg {
         public go.Seq.Ref ref() { return ref; }
         
         public void call(int code, go.Seq in, go.Seq out) {
-            throw new RuntimeException("cycle: cannot call concrete proxy");
+            throw new RuntimeException("internal error: cycle: cannot call concrete proxy");
         }
         
         
@@ -140,7 +142,6 @@ public final class Testpkg {
         }
         
         @Override public String toString() {
-            // TODO(crawshaw): use String() string if it is defined.
             StringBuilder b = new StringBuilder();
             b.append("S").append("{");
             return b.append("}").toString();
@@ -155,6 +156,4 @@ public final class Testpkg {
     private static final int CALL_New = 5;
     private static final int CALL_NumSCollected = 6;
     private static final String DESCRIPTOR = "testpkg";
-    
-    public static Testpkg instance = new Testpkg();
 }
diff --git a/bind/java/testpkg/go_testpkg/go_testpkg.go b/bind/java/testpkg/go_testpkg/go_testpkg.go
index 03f7e1d..8cb9a60 100644
--- a/bind/java/testpkg/go_testpkg/go_testpkg.go
+++ b/bind/java/testpkg/go_testpkg/go_testpkg.go
@@ -1,7 +1,7 @@
 // Package go_testpkg is an autogenerated binder stub for package testpkg.
+//   gobind -lang=go code.google.com/p/go.mobile/bind/java/testpkg
 //
 // File is generated by gobind. Do not edit.
-// Or do, I'm a comment, not a cop.
 package go_testpkg
 
 import (
@@ -13,7 +13,6 @@ func proxy_Add(out, in *seq.Buffer) {
 	param_x := in.ReadInt()
 	param_y := in.ReadInt()
 	res := testpkg.Add(param_x, param_y)
-	// TODO out.WriteNoException();
 	out.WriteInt(res)
 }
 
@@ -26,24 +25,21 @@ func proxy_Call(out, in *seq.Buffer) {
 		param_i = (*proxyI)(param_i_ref)
 	}
 	testpkg.Call(param_i)
-	// TODO out.WriteNoException();
 }
 
 func proxy_GC(out, in *seq.Buffer) {
 	testpkg.GC()
-	// TODO out.WriteNoException();
 }
 
 const (
 	proxyIDescriptor = "go.testpkg.I"
-	proxyIFCode      = 0x0a01
+	proxyIFCode      = 0x10a
 )
 
 type proxyI seq.Ref
 
 func (p *proxyI) F() {
 	out := new(seq.Buffer)
-	//out.WriteRef((*seq.Ref)(p))
 	seq.Transact((*seq.Ref)(p), proxyIFCode, out)
 }
 
@@ -56,24 +52,21 @@ func proxy_Keep(out, in *seq.Buffer) {
 		param_i = (*proxyI)(param_i_ref)
 	}
 	testpkg.Keep(param_i)
-	// TODO out.WriteNoException();
 }
 
 func proxy_New(out, in *seq.Buffer) {
 	res := testpkg.New()
-	// TODO out.WriteNoException();
 	out.WriteGoRef(res)
 }
 
 func proxy_NumSCollected(out, in *seq.Buffer) {
 	res := testpkg.NumSCollected()
-	// TODO out.WriteNoException();
 	out.WriteInt(res)
 }
 
 const (
 	proxySDescriptor = "go.testpkg.S"
-	proxySFCode      = 0x0c00
+	proxySFCode      = 0x00c
 )
 
 type proxyS seq.Ref
@@ -82,7 +75,6 @@ func proxySF(out, in *seq.Buffer) {
 	ref := in.ReadRef()
 	v := ref.Get().(*testpkg.S)
 	v.F()
-	// TODO out.WriteNoException();
 }
 
 func init() {
diff --git a/bind/testdata/basictypes.go.golden b/bind/testdata/basictypes.go.golden
index 32a4f10..b24898b 100644
--- a/bind/testdata/basictypes.go.golden
+++ b/bind/testdata/basictypes.go.golden
@@ -1,11 +1,12 @@
 // Package go_basictypes is an autogenerated binder stub for package basictypes.
+//   gobind -lang=go basictypes
 //
 // File is generated by gobind. Do not edit.
 package go_basictypes
 
 import (
 	"basictypes"
-	"code.google.com/p/go.mobile/bind/seq"
+	"golang.org/x/mobile/bind/seq"
 )
 
 func proxy_Error(out, in *seq.Buffer) {
diff --git a/bind/testdata/basictypes.java.golden b/bind/testdata/basictypes.java.golden
index 675512a..56ede5d 100644
--- a/bind/testdata/basictypes.java.golden
+++ b/bind/testdata/basictypes.java.golden
@@ -1,4 +1,5 @@
 // Java Package basictypes is a proxy for talking to a Go program.
+//   gobind -lang=java basictypes
 //
 // File is generated by gobind. Do not edit.
 package go.basictypes;
diff --git a/bind/testdata/interfaces.go.golden b/bind/testdata/interfaces.go.golden
index 73e6327..e72cdcc 100644
--- a/bind/testdata/interfaces.go.golden
+++ b/bind/testdata/interfaces.go.golden
@@ -1,10 +1,11 @@
 // Package go_interfaces is an autogenerated binder stub for package interfaces.
+//   gobind -lang=go interfaces
 //
 // File is generated by gobind. Do not edit.
 package go_interfaces
 
 import (
-	"code.google.com/p/go.mobile/bind/seq"
+	"golang.org/x/mobile/bind/seq"
 	"interfaces"
 )
 
diff --git a/bind/testdata/interfaces.java.golden b/bind/testdata/interfaces.java.golden
index 45afaa4..9d0a72d 100644
--- a/bind/testdata/interfaces.java.golden
+++ b/bind/testdata/interfaces.java.golden
@@ -1,4 +1,5 @@
 // Java Package interfaces is a proxy for talking to a Go program.
+//   gobind -lang=java interfaces
 //
 // File is generated by gobind. Do not edit.
 package go.interfaces;
diff --git a/bind/testdata/structs.go.golden b/bind/testdata/structs.go.golden
index 7e879fa..b32ec0d 100644
--- a/bind/testdata/structs.go.golden
+++ b/bind/testdata/structs.go.golden
@@ -1,10 +1,11 @@
 // Package go_structs is an autogenerated binder stub for package structs.
+//   gobind -lang=go structs
 //
 // File is generated by gobind. Do not edit.
 package go_structs
 
 import (
-	"code.google.com/p/go.mobile/bind/seq"
+	"golang.org/x/mobile/bind/seq"
 	"structs"
 )
 
diff --git a/bind/testdata/structs.java.golden b/bind/testdata/structs.java.golden
index 9cd0777..ced08fe 100644
--- a/bind/testdata/structs.java.golden
+++ b/bind/testdata/structs.java.golden
@@ -1,4 +1,5 @@
 // Java Package structs is a proxy for talking to a Go program.
+//   gobind -lang=java structs
 //
 // File is generated by gobind. Do not edit.
 package go.structs;
diff --git a/example/libhello/hi/go_hi/go_hi.go b/example/libhello/hi/go_hi/go_hi.go
index 295f96a..b3cb80b 100644
--- a/example/libhello/hi/go_hi/go_hi.go
+++ b/example/libhello/hi/go_hi/go_hi.go
@@ -1,4 +1,5 @@
 // Package go_hi is an autogenerated binder stub for package hi.
+//   gobind -lang=go code.google.com/p/go.mobile/example/libhello/hi
 //
 // File is generated by gobind. Do not edit.
 package go_hi