diff -r 80b9cc90b643 -r 9793f47cdebc make/windows/makefiles/defs.make
--- a/make/windows/makefiles/defs.make	Tue May 15 11:27:24 2012 -0700
+++ b/make/windows/makefiles/defs.make	Tue May 15 15:16:14 2012 -0700
@@ -143,9 +143,7 @@
 MAKE_ARGS += ENABLE_FULL_DEBUG_SYMBOLS=$(ENABLE_FULL_DEBUG_SYMBOLS)
 
 ifeq ($(ENABLE_FULL_DEBUG_SYMBOLS),1)
-  # Disable ZIP_DEBUGINFO_FILES by default because various tests are
-  # failing in nightly when the debug info files are ZIP'ed.
-  ZIP_DEBUGINFO_FILES ?= 0
+  ZIP_DEBUGINFO_FILES ?= 1
 else
   ZIP_DEBUGINFO_FILES=0
 endif