diff --git a/nsprpub/TAG-INFO b/nsprpub/TAG-INFO
index 4436a363173..a5fbfe55505 100644
--- a/nsprpub/TAG-INFO
+++ b/nsprpub/TAG-INFO
@@ -1 +1 @@
-NSPR_4_9_1_RTM
+NSPR_4_9_2_BETA1
diff --git a/nsprpub/admin/repackage.sh b/nsprpub/admin/repackage.sh
index 8a2b367a4f8..2f84803c8e3 100755
--- a/nsprpub/admin/repackage.sh
+++ b/nsprpub/admin/repackage.sh
@@ -32,10 +32,10 @@
 # 
 # ------------------------------------------------------------------
 
-FROMTOP=/share/builds/components/nspr20/v4.9.1
-TOTOP=./v4.9.1
-NSPRDIR=nspr-4.9.1
-SOURCETAG=NSPR_4_9_1_RTM
+FROMTOP=/share/builds/components/nspr20/v4.9.2
+TOTOP=./v4.9.2
+NSPRDIR=nspr-4.9.2
+SOURCETAG=NSPR_4_9_2_RTM
 
 #
 # enumerate Unix object directories on /s/b/c
diff --git a/nsprpub/config/prdepend.h b/nsprpub/config/prdepend.h
index 6c66b37ca0f..e49e92677e3 100644
--- a/nsprpub/config/prdepend.h
+++ b/nsprpub/config/prdepend.h
@@ -10,4 +10,3 @@
  */
 
 #error "Do not include this header file."
-
diff --git a/nsprpub/configure b/nsprpub/configure
index 140225c1a32..7493615cb69 100755
--- a/nsprpub/configure
+++ b/nsprpub/configure
@@ -736,7 +736,7 @@ test "$host_alias" != "$target_alias" &&
 
 MOD_MAJOR_VERSION=4
 MOD_MINOR_VERSION=9
-MOD_PATCH_VERSION=1
+MOD_PATCH_VERSION=2
 NSPR_MODNAME=nspr20
 _HAVE_PTHREADS=
 USE_PTHREADS=
diff --git a/nsprpub/configure.in b/nsprpub/configure.in
index 285506df8bc..da7961c9a72 100644
--- a/nsprpub/configure.in
+++ b/nsprpub/configure.in
@@ -15,7 +15,7 @@ dnl = Defaults
 dnl ========================================================
 MOD_MAJOR_VERSION=4
 MOD_MINOR_VERSION=9
-MOD_PATCH_VERSION=1
+MOD_PATCH_VERSION=2
 NSPR_MODNAME=nspr20
 _HAVE_PTHREADS=
 USE_PTHREADS=
diff --git a/nsprpub/pr/include/md/_win95.h b/nsprpub/pr/include/md/_win95.h
index b3b88bd3d6b..a919e3a02e6 100644
--- a/nsprpub/pr/include/md/_win95.h
+++ b/nsprpub/pr/include/md/_win95.h
@@ -362,6 +362,7 @@ extern PROsfd _MD_Accept(PRFileDesc *fd, PRNetAddr *raddr, PRUint32 *rlen,
 #define _MD_CREATE_THREAD           _PR_MD_CREATE_THREAD
 #define _MD_YIELD                   _PR_MD_YIELD
 #define _MD_SET_PRIORITY            _PR_MD_SET_PRIORITY
+#define _MD_SET_CURRENT_THREAD_NAME _PR_MD_SET_CURRENT_THREAD_NAME
 #define _MD_CLEAN_THREAD            _PR_MD_CLEAN_THREAD
 #define _MD_SETTHREADAFFINITYMASK   _PR_MD_SETTHREADAFFINITYMASK
 #define _MD_GETTHREADAFFINITYMASK   _PR_MD_GETTHREADAFFINITYMASK
diff --git a/nsprpub/pr/include/md/_winnt.h b/nsprpub/pr/include/md/_winnt.h
index 57423eacd9a..4d4d2c12709 100644
--- a/nsprpub/pr/include/md/_winnt.h
+++ b/nsprpub/pr/include/md/_winnt.h
@@ -376,6 +376,7 @@ extern int _PR_NTFiberSafeSelect(int, fd_set *, fd_set *, fd_set *,
 #define _MD_END_THREAD              _PR_MD_END_THREAD
 #define _MD_YIELD                   _PR_MD_YIELD
 #define _MD_SET_PRIORITY            _PR_MD_SET_PRIORITY
+#define _MD_SET_CURRENT_THREAD_NAME _PR_MD_SET_CURRENT_THREAD_NAME
 #define _MD_CLEAN_THREAD            _PR_MD_CLEAN_THREAD
 #define _MD_SETTHREADAFFINITYMASK   _PR_MD_SETTHREADAFFINITYMASK
 #define _MD_GETTHREADAFFINITYMASK   _PR_MD_GETTHREADAFFINITYMASK
diff --git a/nsprpub/pr/include/prinit.h b/nsprpub/pr/include/prinit.h
index edbb2af4c96..c1100997319 100644
--- a/nsprpub/pr/include/prinit.h
+++ b/nsprpub/pr/include/prinit.h
@@ -31,11 +31,11 @@ PR_BEGIN_EXTERN_C
 ** The format of the version string is
 **     "<major version>.<minor version>[.<patch level>] [<Beta>]"
 */
-#define PR_VERSION  "4.9.1"
+#define PR_VERSION  "4.9.2 Beta"
 #define PR_VMAJOR   4
 #define PR_VMINOR   9
-#define PR_VPATCH   1
-#define PR_BETA     PR_FALSE
+#define PR_VPATCH   2
+#define PR_BETA     PR_TRUE
 
 /*
 ** PRVersionCheck
diff --git a/nsprpub/pr/include/private/primpl.h b/nsprpub/pr/include/private/primpl.h
index d86f66f71b3..e9217f29db7 100644
--- a/nsprpub/pr/include/private/primpl.h
+++ b/nsprpub/pr/include/private/primpl.h
@@ -977,6 +977,9 @@ extern void _PR_MD_YIELD(void);
 extern void _PR_MD_SET_PRIORITY(_MDThread *md, PRThreadPriority newPri);
 #define    _PR_MD_SET_PRIORITY _MD_SET_PRIORITY
 
+extern void _PR_MD_SET_CURRENT_THREAD_NAME(const char *name);
+#define    _PR_MD_SET_CURRENT_THREAD_NAME _MD_SET_CURRENT_THREAD_NAME
+
 NSPR_API(void) _PR_MD_SUSPENDALL(void);
 #define    _PR_MD_SUSPENDALL _MD_SUSPENDALL
 
@@ -1533,6 +1536,7 @@ struct PRThread {
     PRIntn  errorStringLength;      /* textLength from last call to PR_SetErrorText() */
     PRInt32 errorStringSize;        /* malloc()'d size of buffer | zero */
     char *errorString;              /* current error string | NULL */
+    char *name;                     /* thread's name */
 
 #if defined(_PR_PTHREADS)
     pthread_t id;                   /* pthread identifier for the thread */
diff --git a/nsprpub/pr/include/prthread.h b/nsprpub/pr/include/prthread.h
index f38ff69c8d9..708c889c74b 100644
--- a/nsprpub/pr/include/prthread.h
+++ b/nsprpub/pr/include/prthread.h
@@ -144,6 +144,17 @@ NSPR_API(PRThreadPriority) PR_GetThreadPriority(const PRThread *thread);
 */
 NSPR_API(void) PR_SetThreadPriority(PRThread *thread, PRThreadPriority priority);
 
+/*
+** Set the name of the current thread, which will be visible in a debugger
+** and accessible via a call to PR_GetThreadName().
+*/
+NSPR_API(PRStatus) PR_SetCurrentThreadName(const char *name);
+
+/*
+** Return the name of "thread", if set.  Otherwise return NULL.
+*/
+NSPR_API(const char *) PR_GetThreadName(const PRThread *thread);
+
 /*
 ** This routine returns a new index for per-thread-private data table. 
 ** The index is visible to all threads within a process. This index can 
diff --git a/nsprpub/pr/src/md/windows/ntthread.c b/nsprpub/pr/src/md/windows/ntthread.c
index 5f9e646377e..d695fe40e85 100644
--- a/nsprpub/pr/src/md/windows/ntthread.c
+++ b/nsprpub/pr/src/md/windows/ntthread.c
@@ -276,6 +276,40 @@ _PR_MD_SET_PRIORITY(_MDThread *thread, PRThreadPriority newPri)
     return;
 }
 
+const DWORD MS_VC_EXCEPTION = 0x406D1388;
+
+#pragma pack(push,8)
+typedef struct tagTHREADNAME_INFO
+{
+   DWORD dwType; // Must be 0x1000.
+   LPCSTR szName; // Pointer to name (in user addr space).
+   DWORD dwThreadID; // Thread ID (-1=caller thread).
+   DWORD dwFlags; // Reserved for future use, must be zero.
+} THREADNAME_INFO;
+#pragma pack(pop)
+
+void
+_PR_MD_SET_CURRENT_THREAD_NAME(const char *name)
+{
+   THREADNAME_INFO info;
+
+   if (!IsDebuggerPresent())
+      return;
+
+   info.dwType = 0x1000;
+   info.szName = (char*) name;
+   info.dwThreadID = -1;
+   info.dwFlags = 0;
+
+   __try {
+      RaiseException(MS_VC_EXCEPTION,
+                     0,
+                     sizeof(info) / sizeof(ULONG_PTR),
+                     (ULONG_PTR*)&info);
+   } __except(EXCEPTION_CONTINUE_EXECUTION) {
+   }
+}
+
 void
 _PR_MD_CLEAN_THREAD(PRThread *thread)
 {
diff --git a/nsprpub/pr/src/md/windows/w95thred.c b/nsprpub/pr/src/md/windows/w95thred.c
index dc0eac31bcf..21b4a6eac25 100644
--- a/nsprpub/pr/src/md/windows/w95thred.c
+++ b/nsprpub/pr/src/md/windows/w95thred.c
@@ -168,6 +168,40 @@ _PR_MD_SET_PRIORITY(_MDThread *thread, PRThreadPriority newPri)
     return;
 }
 
+const DWORD MS_VC_EXCEPTION = 0x406D1388;
+
+#pragma pack(push,8)
+typedef struct tagTHREADNAME_INFO
+{
+   DWORD dwType; // Must be 0x1000.
+   LPCSTR szName; // Pointer to name (in user addr space).
+   DWORD dwThreadID; // Thread ID (-1=caller thread).
+   DWORD dwFlags; // Reserved for future use, must be zero.
+} THREADNAME_INFO;
+#pragma pack(pop)
+
+void
+_PR_MD_SET_CURRENT_THREAD_NAME(const char *name)
+{
+   THREADNAME_INFO info;
+
+   if (!IsDebuggerPresent())
+      return;
+
+   info.dwType = 0x1000;
+   info.szName = (char*) name;
+   info.dwThreadID = -1;
+   info.dwFlags = 0;
+
+   __try {
+      RaiseException(MS_VC_EXCEPTION,
+                     0,
+                     sizeof(info) / sizeof(ULONG_PTR),
+                     (ULONG_PTR*)&info);
+   } __except(EXCEPTION_CONTINUE_EXECUTION) {
+   }
+}
+
 void
 _PR_MD_CLEAN_THREAD(PRThread *thread)
 {
diff --git a/nsprpub/pr/src/nspr.def b/nsprpub/pr/src/nspr.def
index c6618a8d444..7777a3dbe33 100644
--- a/nsprpub/pr/src/nspr.def
+++ b/nsprpub/pr/src/nspr.def
@@ -446,3 +446,8 @@ EXPORTS ;-
 ;+      global:
                 PR_GetVersion;
 ;+} NSPR_4.8;
+;+NSPR_4.9.2 {
+;+      global:
+		PR_GetThreadName;
+		PR_SetCurrentThreadName;
+;+} NSPR_4.8.9;
diff --git a/nsprpub/pr/src/pthreads/ptthread.c b/nsprpub/pr/src/pthreads/ptthread.c
index c3223bbedab..34c0bb12dca 100644
--- a/nsprpub/pr/src/pthreads/ptthread.c
+++ b/nsprpub/pr/src/pthreads/ptthread.c
@@ -19,6 +19,7 @@
 #include <unistd.h>
 #include <string.h>
 #include <signal.h>
+#include <dlfcn.h>
 
 #ifdef SYMBIAN
 /* In Open C sched_get_priority_min/max do not work properly, so we undefine
@@ -794,6 +795,8 @@ static void _pt_thread_death_internal(void *arg, PRBool callDestructors)
     PR_Free(thred->privateData);
     if (NULL != thred->errorString)
         PR_Free(thred->errorString);
+    if (NULL != thred->name)
+        PR_Free(thred->name);
     PR_Free(thred->stack);
     if (NULL != thred->syspoll_list)
         PR_Free(thred->syspoll_list);
@@ -1612,6 +1615,76 @@ PR_IMPLEMENT(void*)PR_GetSP(PRThread *thred)
 
 #endif /* !defined(_PR_DCETHREADS) */
 
+PR_IMPLEMENT(PRStatus) PR_SetCurrentThreadName(const char *name)
+{
+    PRThread *thread;
+    size_t nameLen;
+    int result;
+
+    if (!name) {
+        PR_SetError(PR_INVALID_ARGUMENT_ERROR, 0);
+        return PR_FAILURE;
+    }
+
+    thread = PR_GetCurrentThread();
+    if (!thread)
+        return PR_FAILURE;
+
+    PR_Free(thread->name);
+    nameLen = strlen(name) + 1;
+    thread->name = (char *)PR_Malloc(nameLen);
+    if (!thread->name)
+        return PR_FAILURE;
+    memcpy(thread->name, name, nameLen);
+
+#if defined(OPENBSD) || defined(FREEBSD)
+    result = pthread_set_name_np(thread->id, name);
+#else /* not BSD */
+    /*
+     * On OSX, pthread_setname_np is only available in 10.6 or later, so test
+     * for it at runtime.  It also may not be available on all linux distros.
+     * The name length limit is 16 bytes.
+     */
+#if defined(DARWIN)
+    int (*dynamic_pthread_setname_np)(const char*);
+#else
+    int (*dynamic_pthread_setname_np)(pthread_t, const char*);
+#endif
+
+    *(void**)(&dynamic_pthread_setname_np) =
+        dlsym(RTLD_DEFAULT, "pthread_setname_np");
+    if (!dynamic_pthread_setname_np)
+        return PR_SUCCESS;
+
+#define SETNAME_LENGTH_CONSTRAINT 15
+    char name_dup[SETNAME_LENGTH_CONSTRAINT + 1];
+    if (nameLen > SETNAME_LENGTH_CONSTRAINT + 1) {
+        memcpy(name_dup, name, SETNAME_LENGTH_CONSTRAINT);
+        name_dup[SETNAME_LENGTH_CONSTRAINT] = '\0';
+        name = name_dup;
+    }
+
+#if defined(DARWIN)
+    result = dynamic_pthread_setname_np(name);
+#else
+    result = dynamic_pthread_setname_np(thread->id, name);
+#endif
+#endif /* not BSD */
+
+    if (result) {
+        PR_SetError(PR_UNKNOWN_ERROR, result);
+        return PR_FAILURE;
+    }
+    return PR_SUCCESS;
+}
+
+PR_IMPLEMENT(const char *) PR_GetThreadName(const PRThread *thread)
+{
+    if (!thread)
+        return NULL;
+    return thread->name;
+}
+
 #endif  /* defined(_PR_PTHREADS) || defined(_PR_DCETHREADS) */
 
 /* ptthread.c */
diff --git a/nsprpub/pr/src/threads/combined/pruthr.c b/nsprpub/pr/src/threads/combined/pruthr.c
index 53eea1fc488..fa5f5209854 100644
--- a/nsprpub/pr/src/threads/combined/pruthr.c
+++ b/nsprpub/pr/src/threads/combined/pruthr.c
@@ -237,6 +237,7 @@ static void _PR_InitializeRecycledThread(PRThread *thread)
     PR_ASSERT(thread->dumpArg == 0 && thread->dump == 0);
     PR_ASSERT(thread->errorString == 0 && thread->errorStringSize == 0);
     PR_ASSERT(thread->errorStringLength == 0);
+    PR_ASSERT(thread->name == 0);
 
     /* Reset data members in thread structure */
     thread->errorCode = thread->osErrorCode = 0;
@@ -1581,6 +1582,37 @@ PR_IMPLEMENT(void) PR_SetThreadPriority(PRThread *thread,
     } else _PR_SetThreadPriority(thread, newPri);
 }
 
+PR_IMPLEMENT(PRStatus) PR_SetCurrentThreadName(const char *name)
+{
+    PRThread *thread;
+    size_t nameLen;
+
+    if (!name) {
+        PR_SetError(PR_INVALID_ARGUMENT_ERROR, 0);
+        return PR_FAILURE;
+    }
+
+    thread = PR_GetCurrentThread();
+    if (!thread)
+        return PR_FAILURE;
+
+    PR_Free(thread->name);
+    nameLen = strlen(name) + 1;
+    thread->name = (char *)PR_Malloc(nameLen);
+    if (!thread->name)
+        return PR_FAILURE;
+    memcpy(thread->name, name, nameLen);
+    _PR_MD_SET_CURRENT_THREAD_NAME(thread->name);
+    return PR_SUCCESS;
+}
+
+PR_IMPLEMENT(const char *) PR_GetThreadName(const PRThread *thread)
+{
+    if (!thread)
+        return NULL;
+    return thread->name;
+}
+
 
 /*
 ** This routine prevents all other threads from running. This call is needed by 
diff --git a/nsprpub/pr/src/threads/prcthr.c b/nsprpub/pr/src/threads/prcthr.c
index 4f9a3beb446..268814473e1 100644
--- a/nsprpub/pr/src/threads/prcthr.c
+++ b/nsprpub/pr/src/threads/prcthr.c
@@ -35,6 +35,7 @@ void _PR_CleanupThread(PRThread *thread)
     }
     thread->dump = 0;
 
+    PR_DELETE(thread->name);
     PR_DELETE(thread->errorString);
     thread->errorStringSize = 0;
     thread->errorStringLength = 0;
diff --git a/nsprpub/pr/tests/vercheck.c b/nsprpub/pr/tests/vercheck.c
index 415caae05e1..2f42523b52f 100644
--- a/nsprpub/pr/tests/vercheck.c
+++ b/nsprpub/pr/tests/vercheck.c
@@ -20,9 +20,10 @@
 #include <stdlib.h>
 
 /*
- * This release (4.9.1) is backward compatible with the
+ * This release (4.9.2) is backward compatible with the
  * 4.0.x, 4.1.x, 4.2.x, 4.3.x, 4.4.x, 4.5.x, 4.6.x, 4.7.x,
- * 4.8.x, and 4.9 releases.  It, of course, is compatible with itself.
+ * 4.8.x, 4.9, and 4.9.1 releases.  It, of course,
+ * is compatible with itself.
  */
 static char *compatible_version[] = {
     "4.0", "4.0.1", "4.1", "4.1.1", "4.1.2", "4.1.3",
@@ -34,7 +35,7 @@ static char *compatible_version[] = {
     "4.7.6",
     "4.8", "4.8.1", "4.8.2", "4.8.3", "4.8.4", "4.8.5",
     "4.8.6", "4.8.7", "4.8.8", "4.8.9",
-    "4.9", PR_VERSION
+    "4.9", "4.9.1", PR_VERSION
 };
 
 /*
@@ -49,7 +50,7 @@ static char *incompatible_version[] = {
     "3.0", "3.0.1",
     "3.1", "3.1.1", "3.1.2", "3.1.3",
     "3.5", "3.5.1",
-    "4.9.2",
+    "4.9.3",
     "4.10", "4.10.1",
     "10.0", "11.1", "12.14.20"
 };