Options panel loses focus when selected

There’s a suite of WP themes I’ve been using; no matter which theme I choose, whenever I select the Theme Options in the Appearance sidebar, if I have another browser window open, that window ends up in front, so that I then have to move it aside and find the panel again.

I have a Mac with Snow Leopard. It happens both with Firefox and Safari, but not in Google Chrome. From what i read in the support forum for those themes, it happens on PCs as well.

Unfortunately, the developer can’t seem to replicate the problem on his computer.

I have looked at how he has coded the call to link the Options into the WP admin panel, and it seems straight forward.

What might possibly be causing this to happen?
What part of the code should I look in?