Yesterday I had troubles to get an ASP.NET control to work with rounded corners in various browsers. IE and Firefox operate slightly different from each other, and to get it working (using ASP.NET themes) was quite a pain in the ass. Besides, it is not cool to have the obligation to change 4 images per control every time the design team has the bright idea to change website colors for some very good reason.
Luckily, at the end of the day, I discovered DD_roundies, a Javascript library perfectly taking care of my needs. Only in Opera this functionality does not function as wanted (no rounded corners), but that’s an issue Drew Diller is trying to address, according to his website. I definitely would suggest you to try for yourself if you would like an acceptable solution to the problem described hereabove.
The only thing that does not currently stop bothering me: unfortunately it is (still) not possible to have some javascript in an ASP.NET theme. Would that be possible, the solution would be perfect (for me). Perhaps somebody found a solution for me ?