Bug 780976 - linux external api builds broken (hidden symbol `MOZ_Z_inflate' isn't defined) since bug 763651. r=neil

mailnews/import/build/Makefile.in

@@ -87,6 +87,12 @@ EXTRA_DSO_LDOPTS += \
 	$(NSPR_LIBS) \
 	$(XPCOM_LIBS) \
 	$(NULL)
+ifneq (WINNT,$(OS_ARCH))
+EXTRA_DSO_LDOPTS += \
+	$(ZLIB_LIBS) \
+	$(MOZ_ZLIB_LIBS) \
+	$(NULL)
+endif
 endif
 
 ifeq (cocoa,$(MOZ_WIDGET_TOOLKIT))