Make sure we're not using a shell version of echo without -e switch

extras/contrib/Makefile

@@ -112,7 +112,7 @@ package-win32: FORCE
 # Hack for qt4
 	(cd tmp/$(DISTDIR)/bin; mv uic.ex uic.exe; mv rcc.ex rcc.exe; mv moc.ex moc.exe)
 # Tar it.
-	(cd tmp; tar cf - $(DISTDIR)) | bzip2 -c > contrib-`date +%Y%m%d`-win32-bin-gcc-`$(CC) --version|head -n 1|cut -f 3 -d ' '`-runtime-`echo -e "#include <_mingw.h>\n__MINGW32_VERSION"|$(CC) -E -|grep -v ^#`-only.tar.bz2
+	(cd tmp; tar cf - $(DISTDIR)) | bzip2 -c > contrib-`date +%Y%m%d`-win32-bin-gcc-`$(CC) --version|head -n 1|cut -f 3 -d ' '`-runtime-`/bin/echo -e "#include <_mingw.h>\n__MINGW32_VERSION"|$(CC) -E -|grep -v ^#|grep -v ' '`-only.tar.bz2
 	rm -rf tmp
 FORCE: