diff --git a/mozilla/xpcom/build/Makefile.in b/mozilla/xpcom/build/Makefile.in
index eaf56ec5543..8a9df0107a3 100644
--- a/mozilla/xpcom/build/Makefile.in
+++ b/mozilla/xpcom/build/Makefile.in
@@ -108,6 +108,10 @@ ifeq ($(MOZ_OS2_TOOLS),VACPP)
 OS_LIBS += libconv.lib libuls.lib
 endif
 
+ifeq ($(MOZ_OS2_TOOLS),EMX)
+OS_LIBS += -luconv
+endif
+
 # UNIX98 iconv support
 OS_LIBS += $(LIBICONV)
 
diff --git a/mozilla/xpcom/glue/nsDebug.cpp b/mozilla/xpcom/glue/nsDebug.cpp
index 02b85256406..1cf6d382f57 100644
--- a/mozilla/xpcom/glue/nsDebug.cpp
+++ b/mozilla/xpcom/glue/nsDebug.cpp
@@ -18,15 +18,8 @@
  * Rights Reserved.
  *
  * Contributor(s): 
- *
- * This Original Code has been modified by IBM Corporation. Modifications made by IBM
- * described herein are Copyright (c) International Business Machines Corporation, 2000.
- * Modifications to Mozilla code or documentation identified per MPL Section 3.3
- *
- * Date        Modified by     Description of modification
- * 04/10/2000  IBM Corp.       Added DebugBreak() definitions for OS/2
- * 06/19/2000  IBM Corp.       Fix DebugBreak() messagebox defaults for OS/2 
- * 06/19/2000  Henry Sobotka Fix DebugBreak() for OS/2 on retail build.
+ *   IBM Corp.
+ *   Henry Sobotka
  */
 
 #include "nsDebug.h"
@@ -64,28 +57,25 @@
 #endif
 
 #if defined(XP_OS2)
-/* Added definitions for DebugBreak() for 2 different OS/2 compilers.  Doing
- * the int3 on purpose for Visual Age so that a developer can step over the
- * instruction if so desired.  Not always possible if trapping due to exception
- * handling IBM-AKR
- */
-#define INCL_WINDIALOGS  // need for WinMessageBox
-#include <os2.h>
-
-#if defined(DEBUG)
-#if defined(XP_OS2_VACPP)
-   #include <builtin.h>
-   #define DebugBreak() { _interrupt(3); }
-#elif defined(XP_OS2_EMX)
-   /* Force a trap */
-   #define DebugBreak() { int *pTrap=NULL; *pTrap = 1; }
-#else
-   #define DebugBreak()
-#endif
-
-#else
-   #define DebugBreak()
-#endif /* DEBUG */
+  /* Added definitions for DebugBreak() for 2 different OS/2 compilers.  Doing
+   * the int3 on purpose for Visual Age so that a developer can step over the
+   * instruction if so desired.  Not always possible if trapping due to exception
+   * handling IBM-AKR
+   */
+  #define INCL_WINDIALOGS  // need for WinMessageBox
+  #include <os2.h>
+  #include <string.h>
+  
+  #if defined(DEBUG)
+   #if defined(XP_OS2_VACPP)
+    #include <builtin.h>
+    #define DebugBreak() { _interrupt(3); }
+   #else
+    #define DebugBreak() { asm("int $3"); }
+   #endif
+  #else
+    #define DebugBreak()
+  #endif /* DEBUG */
 #endif /* XP_OS2 */
 
 #if defined(_WIN32)
diff --git a/mozilla/xpcom/io/nsNativeCharsetUtils.cpp b/mozilla/xpcom/io/nsNativeCharsetUtils.cpp
index 98f28c883b0..f9433ba0b36 100644
--- a/mozilla/xpcom/io/nsNativeCharsetUtils.cpp
+++ b/mozilla/xpcom/io/nsNativeCharsetUtils.cpp
@@ -950,6 +950,10 @@ NS_ShutdownNativeCharsetUtils()
 #include <uconv.h>
 #include "nsPromiseFlatString.h"
 
+#ifdef XP_OS2_EMX
+#include <ulserr.h>
+#endif
+
 static UconvObject UnicodeConverter = NULL;
 
 NS_COM nsresult
diff --git a/mozilla/xpcom/threads/plevent.c b/mozilla/xpcom/threads/plevent.c
index d98d717efaa..cd4c39dc658 100644
--- a/mozilla/xpcom/threads/plevent.c
+++ b/mozilla/xpcom/threads/plevent.c
@@ -1468,6 +1468,16 @@ static void _md_CreateEventQueue( PLEventQueue *eventQueue )
 #endif /* Winxx */
 
 #if defined(XP_OS2)
+/* These functions/values are defined in the EMX libraries, but are not declared
+   in the GCC 3.2.1 headers.  */
+#ifdef XP_OS2_EMX
+unsigned _control87 (unsigned, unsigned);
+#define MCW_EM  0x003f
+#define MCW_IC  0x1000
+#define MCW_RC  0x0c00
+#define MCW_PC  0x0300
+#endif
+
 /*
 ** _md_CreateEventQueue() -- ModelDependent initializer
 */
@@ -1476,8 +1486,22 @@ static void _md_CreateEventQueue( PLEventQueue *eventQueue )
     /* Must have HMQ for this & can't assume we already have appshell */
     if( FALSE == WinQueryQueueInfo( HMQ_CURRENT, NULL, 0))
     {
+       unsigned cw;
+       
        HAB hab = WinInitialize( 0);
+       
+#ifdef XP_OS2_EMX
+       /* It seems that WinCreateMsgQueue likes to change the floating point
+          control word for undocumented reasons.  Unfortunately, it causes
+          floating point exceptions (SIGFPE) to be unmasked, so we crash in 
+          javascript on startup.  The two calls to _control87 simply save the
+          current value of the control word and resets it after the call */
+       cw = _control87(0,0);
+#endif
        WinCreateMsgQueue( hab, 0);
+#ifdef XP_OS2_EMX
+       _control87(cw, MCW_EM | MCW_IC | MCW_RC | MCW_PC);
+#endif
     }
 
     if( !_pr_PostEventMsgId)