panels rounded-shadow-top-edge ie7 bug how fix ?

Hi
I have a problem with panels
i have a transparent line on top of my panels in ie7. in ff and ie8 its works great.
Here is a snapshot of my problem with ie7:

http://phuyatta.home.pl/intymnie/ie7problem.gif

So is here anyone who have this problem and fix them ? Please help me.
I try on polish board but no one can help me.