diff --git a/nsprpub/pr/include/private/primpl.h b/nsprpub/pr/include/private/primpl.h
index 424d0f1e36d..826dc716279 100644
--- a/nsprpub/pr/include/private/primpl.h
+++ b/nsprpub/pr/include/private/primpl.h
@@ -1735,6 +1735,7 @@ extern void _PR_InitMW(void);
 extern void _PR_InitRWLocks(void);
 extern void _PR_NotifyCondVar(PRCondVar *cvar, PRThread *me);
 extern void _PR_CleanupThread(PRThread *thread);
+extern void _PR_CleanupLayerCache(void);
 extern void _PR_CleanupStacks(void);
 extern void _PR_CleanupThreads(void);
 extern void _PR_CleanupTPD(void);
diff --git a/nsprpub/pr/src/io/prlayer.c b/nsprpub/pr/src/io/prlayer.c
index 8cb5cda6a30..d74fa8be4b4 100644
--- a/nsprpub/pr/src/io/prlayer.c
+++ b/nsprpub/pr/src/io/prlayer.c
@@ -743,4 +743,23 @@ void _PR_InitLayerCache()
     PR_ASSERT(NULL != identity_cache.ml);
 }  /* _PR_InitLayerCache */
 
+void _PR_CleanupLayerCache(void)
+{
+    if (identity_cache.ml)
+    {
+        PR_DestroyLock(identity_cache.ml);
+        identity_cache.ml = NULL;
+    }
+
+    if (identity_cache.name)
+    {
+        PRDescIdentity ident;
+
+        for (ident = 0; ident <= identity_cache.ident; ident++)
+            PR_DELETE(identity_cache.name[ident]);
+
+        PR_DELETE(identity_cache.name);
+    }
+}  /* _PR_CleanupLayerCache */
+
 /* prlayer.c */
diff --git a/nsprpub/pr/src/misc/prinit.c b/nsprpub/pr/src/misc/prinit.c
index bfa59fa018e..b9a4b07a4f5 100644
--- a/nsprpub/pr/src/misc/prinit.c
+++ b/nsprpub/pr/src/misc/prinit.c
@@ -447,6 +447,7 @@ PR_IMPLEMENT(PRStatus) PR_Cleanup()
          * _PR_XXXCleanup() that we can call here.
          */
         _PR_CleanupThreads();
+        _PR_CleanupLayerCache();
         _PR_CleanupStacks();
         _PR_CleanupBeforeExit();
         _pr_initialized = PR_FALSE;
diff --git a/nsprpub/pr/src/pthreads/ptthread.c b/nsprpub/pr/src/pthreads/ptthread.c
index c573fe3f73d..3ae5feeeae0 100644
--- a/nsprpub/pr/src/pthreads/ptthread.c
+++ b/nsprpub/pr/src/pthreads/ptthread.c
@@ -936,6 +936,7 @@ PR_IMPLEMENT(PRStatus) PR_Cleanup()
             PR_DestroyLock(pt_book.ml); pt_book.ml = NULL;
         }
         _pt_thread_death(me);
+        _PR_CleanupLayerCache();
         _pr_initialized = PR_FALSE;
         return PR_SUCCESS;
     }