PreferenceActivity background in ics is gone during scroll

i'm using PreferenceActivity in my app for settings and when tried to set a background and it looks fine untill the user scroll. during the scroll there is background only below the text (see links to images below)

after the scroll it goes back to how it was before (the way it should look)

the problem happens only on ics (on nexus one it works fine)


did anyone saw that problem before and know how to fix it?


thanks.

thats how it looks before scrolling http://i.stack.imgur.com/4aPKX.png


and thats how it looks during scrolling http://i.stack.imgur.com/zDbgU.png