diff --git a/xpcom/build/makefile.win b/xpcom/build/makefile.win
index c5a8afb86ea9..575b5718da87 100644
--- a/xpcom/build/makefile.win
+++ b/xpcom/build/makefile.win
@@ -23,6 +23,11 @@ MODULE = xpcom
 LIBNAME = .\$(OBJDIR)\xpcom
 DLL = $(LIBNAME).dll
 
+# if we ever add a .def file for x86 we need to deal with this.
+!if "$(CPU)" == "ALPHA"
+DEFFILE = xpcom_alpha.def
+!endif
+
 LINCS =                          \
         -I$(PUBLIC)\xpcom        \
         -I..\base                \
diff --git a/xpcom/build/xpcom_alpha.def b/xpcom/build/xpcom_alpha.def
new file mode 100644
index 000000000000..9fec5a72e441
--- /dev/null
+++ b/xpcom/build/xpcom_alpha.def
@@ -0,0 +1,134 @@
+LIBRARY xpcom
+DESCRIPTION "xpcom library"
+
+EXPORTS
+    ?Stub3@nsXPTCStubBase@@UAAIXZ
+    ?Stub4@nsXPTCStubBase@@UAAIXZ
+    ?Stub5@nsXPTCStubBase@@UAAIXZ
+    ?Stub6@nsXPTCStubBase@@UAAIXZ
+    ?Stub7@nsXPTCStubBase@@UAAIXZ
+    ?Stub8@nsXPTCStubBase@@UAAIXZ
+    ?Stub9@nsXPTCStubBase@@UAAIXZ
+    ?Stub10@nsXPTCStubBase@@UAAIXZ
+    ?Stub11@nsXPTCStubBase@@UAAIXZ
+    ?Stub12@nsXPTCStubBase@@UAAIXZ
+    ?Stub13@nsXPTCStubBase@@UAAIXZ
+    ?Stub14@nsXPTCStubBase@@UAAIXZ
+    ?Stub15@nsXPTCStubBase@@UAAIXZ
+    ?Stub16@nsXPTCStubBase@@UAAIXZ
+    ?Stub17@nsXPTCStubBase@@UAAIXZ
+    ?Stub18@nsXPTCStubBase@@UAAIXZ
+    ?Stub19@nsXPTCStubBase@@UAAIXZ
+    ?Stub20@nsXPTCStubBase@@UAAIXZ
+    ?Stub21@nsXPTCStubBase@@UAAIXZ
+    ?Stub22@nsXPTCStubBase@@UAAIXZ
+    ?Stub23@nsXPTCStubBase@@UAAIXZ
+    ?Stub24@nsXPTCStubBase@@UAAIXZ
+    ?Stub25@nsXPTCStubBase@@UAAIXZ
+    ?Stub26@nsXPTCStubBase@@UAAIXZ
+    ?Stub27@nsXPTCStubBase@@UAAIXZ
+    ?Stub28@nsXPTCStubBase@@UAAIXZ
+    ?Stub29@nsXPTCStubBase@@UAAIXZ
+    ?Stub30@nsXPTCStubBase@@UAAIXZ
+    ?Stub31@nsXPTCStubBase@@UAAIXZ
+    ?Stub32@nsXPTCStubBase@@UAAIXZ
+    ?Stub33@nsXPTCStubBase@@UAAIXZ
+    ?Stub34@nsXPTCStubBase@@UAAIXZ
+    ?Stub35@nsXPTCStubBase@@UAAIXZ
+    ?Stub36@nsXPTCStubBase@@UAAIXZ
+    ?Stub37@nsXPTCStubBase@@UAAIXZ
+    ?Stub38@nsXPTCStubBase@@UAAIXZ
+    ?Stub39@nsXPTCStubBase@@UAAIXZ
+    ?Stub40@nsXPTCStubBase@@UAAIXZ
+    ?Stub41@nsXPTCStubBase@@UAAIXZ
+    ?Stub42@nsXPTCStubBase@@UAAIXZ
+    ?Stub43@nsXPTCStubBase@@UAAIXZ
+    ?Stub44@nsXPTCStubBase@@UAAIXZ
+    ?Stub45@nsXPTCStubBase@@UAAIXZ
+    ?Stub46@nsXPTCStubBase@@UAAIXZ
+    ?Stub47@nsXPTCStubBase@@UAAIXZ
+    ?Stub48@nsXPTCStubBase@@UAAIXZ
+    ?Stub49@nsXPTCStubBase@@UAAIXZ
+    ?Stub50@nsXPTCStubBase@@UAAIXZ
+    ?Stub51@nsXPTCStubBase@@UAAIXZ
+    ?Stub52@nsXPTCStubBase@@UAAIXZ
+    ?Stub53@nsXPTCStubBase@@UAAIXZ
+    ?Stub54@nsXPTCStubBase@@UAAIXZ
+    ?Stub55@nsXPTCStubBase@@UAAIXZ
+    ?Stub56@nsXPTCStubBase@@UAAIXZ
+    ?Stub57@nsXPTCStubBase@@UAAIXZ
+    ?Stub58@nsXPTCStubBase@@UAAIXZ
+    ?Stub59@nsXPTCStubBase@@UAAIXZ
+    ?Stub60@nsXPTCStubBase@@UAAIXZ
+    ?Stub61@nsXPTCStubBase@@UAAIXZ
+    ?Stub62@nsXPTCStubBase@@UAAIXZ
+    ?Stub63@nsXPTCStubBase@@UAAIXZ
+    ?Stub64@nsXPTCStubBase@@UAAIXZ
+    ?Stub65@nsXPTCStubBase@@UAAIXZ
+    ?Stub66@nsXPTCStubBase@@UAAIXZ
+    ?Stub67@nsXPTCStubBase@@UAAIXZ
+    ?Stub68@nsXPTCStubBase@@UAAIXZ
+    ?Stub69@nsXPTCStubBase@@UAAIXZ
+    ?Stub70@nsXPTCStubBase@@UAAIXZ
+    ?Stub71@nsXPTCStubBase@@UAAIXZ
+    ?Stub72@nsXPTCStubBase@@UAAIXZ
+    ?Stub73@nsXPTCStubBase@@UAAIXZ
+    ?Stub74@nsXPTCStubBase@@UAAIXZ
+    ?Stub75@nsXPTCStubBase@@UAAIXZ
+    ?Stub76@nsXPTCStubBase@@UAAIXZ
+    ?Stub77@nsXPTCStubBase@@UAAIXZ
+    ?Stub78@nsXPTCStubBase@@UAAIXZ
+    ?Stub79@nsXPTCStubBase@@UAAIXZ
+    ?Stub80@nsXPTCStubBase@@UAAIXZ
+    ?Stub81@nsXPTCStubBase@@UAAIXZ
+    ?Stub82@nsXPTCStubBase@@UAAIXZ
+    ?Stub83@nsXPTCStubBase@@UAAIXZ
+    ?Stub84@nsXPTCStubBase@@UAAIXZ
+    ?Stub85@nsXPTCStubBase@@UAAIXZ
+    ?Stub86@nsXPTCStubBase@@UAAIXZ
+    ?Stub87@nsXPTCStubBase@@UAAIXZ
+    ?Stub88@nsXPTCStubBase@@UAAIXZ
+    ?Stub89@nsXPTCStubBase@@UAAIXZ
+    ?Stub90@nsXPTCStubBase@@UAAIXZ
+    ?Stub91@nsXPTCStubBase@@UAAIXZ
+    ?Stub92@nsXPTCStubBase@@UAAIXZ
+    ?Stub93@nsXPTCStubBase@@UAAIXZ
+    ?Stub94@nsXPTCStubBase@@UAAIXZ
+    ?Stub95@nsXPTCStubBase@@UAAIXZ
+    ?Stub96@nsXPTCStubBase@@UAAIXZ
+    ?Stub97@nsXPTCStubBase@@UAAIXZ
+    ?Stub98@nsXPTCStubBase@@UAAIXZ
+    ?Stub99@nsXPTCStubBase@@UAAIXZ
+    ?Stub100@nsXPTCStubBase@@UAAIXZ
+    ?Stub101@nsXPTCStubBase@@UAAIXZ
+    ?Stub102@nsXPTCStubBase@@UAAIXZ
+    ?Stub103@nsXPTCStubBase@@UAAIXZ
+    ?Stub104@nsXPTCStubBase@@UAAIXZ
+    ?Stub105@nsXPTCStubBase@@UAAIXZ
+    ?Stub106@nsXPTCStubBase@@UAAIXZ
+    ?Stub107@nsXPTCStubBase@@UAAIXZ
+    ?Stub108@nsXPTCStubBase@@UAAIXZ
+    ?Stub109@nsXPTCStubBase@@UAAIXZ
+    ?Stub110@nsXPTCStubBase@@UAAIXZ
+    ?Stub111@nsXPTCStubBase@@UAAIXZ
+    ?Stub112@nsXPTCStubBase@@UAAIXZ
+    ?Stub113@nsXPTCStubBase@@UAAIXZ
+    ?Stub114@nsXPTCStubBase@@UAAIXZ
+    ?Stub115@nsXPTCStubBase@@UAAIXZ
+    ?Stub116@nsXPTCStubBase@@UAAIXZ
+    ?Stub117@nsXPTCStubBase@@UAAIXZ
+    ?Stub118@nsXPTCStubBase@@UAAIXZ
+    ?Stub119@nsXPTCStubBase@@UAAIXZ
+    ?Stub120@nsXPTCStubBase@@UAAIXZ
+    ?Stub121@nsXPTCStubBase@@UAAIXZ
+    ?Stub122@nsXPTCStubBase@@UAAIXZ
+    ?Stub123@nsXPTCStubBase@@UAAIXZ
+    ?Stub124@nsXPTCStubBase@@UAAIXZ
+    ?Stub125@nsXPTCStubBase@@UAAIXZ
+    ?Stub126@nsXPTCStubBase@@UAAIXZ
+    ?Stub127@nsXPTCStubBase@@UAAIXZ
+    ?Stub128@nsXPTCStubBase@@UAAIXZ
+    ?Stub129@nsXPTCStubBase@@UAAIXZ
+    ?Stub130@nsXPTCStubBase@@UAAIXZ
+
+