diff --git a/mozilla/modules/plugin/tools/sdk/samples/simple/Makefile.in b/mozilla/modules/plugin/tools/sdk/samples/simple/Makefile.in
index da23b629780..6a273dd3176 100644
--- a/mozilla/modules/plugin/tools/sdk/samples/simple/Makefile.in
+++ b/mozilla/modules/plugin/tools/sdk/samples/simple/Makefile.in
@@ -44,7 +44,7 @@ XPIDLSRCS = nsISimplePlugin.idl
 SHARED_LIBRARY_LIBS = ../common/$(LIB_PREFIX)plugingate_s.$(LIB_SUFFIX)
 
 ifeq ($(OS_ARCH),WINNT)
-DEFFILE = npsimple.def
+DEFFILE = $(srcdir)/npsimple.def
 RESFILE = npsimple.res
 endif