force the uec to be recreated
diff --git a/tools/build_uec.sh b/tools/build_uec.sh
index efae619..0a82103 100755
--- a/tools/build_uec.sh
+++ b/tools/build_uec.sh
@@ -154,6 +154,7 @@
 </domain>
 EOF
 
+rm -rf $vm_dir/uec
 cp -r $TOOLS_DIR/uec $vm_dir/uec
 
 cd $vm_dir/uec