diff --git a/sitespeed.io b/sitespeed.io
index 455643902..4944de4bd 100755
--- a/sitespeed.io
+++ b/sitespeed.io
@@ -99,10 +99,10 @@ do
     echo "Analyzing $i"
     phantomjs dependencies/yslow.js -f xml "$i" >>"$REPORT_DATA_PAGES_DIR/$pagefilename.xml"
     # Sometimes the yslow script adds output before the xml tag, should probably be reported ...
-    sed -i "" '/<?xml/,$!d' $REPORT_DATA_PAGES_DIR/$pagefilename.xml
+    sed -i .bak '/<?xml/,$!d' $REPORT_DATA_PAGES_DIR/$pagefilename.xml
      
     # Hack for adding link to the output file name
-    sed -i "" 's/<results>/<results filename="'$pagefilename'">/g' $REPORT_DATA_PAGES_DIR/$pagefilename.xml 
+    sed -i .bak 's/<results>/<results filename="'$pagefilename'">/g' $REPORT_DATA_PAGES_DIR/$pagefilename.xml 
     sed 's/<?xml version="1.0" encoding="UTF-8"?>//g' "$REPORT_DATA_PAGES_DIR/$pagefilename.xml" >> "$REPORT_DATA_DIR/result.xml"
     pagefilename=$[$pagefilename+1]
 done