SubSim main page issues w/ Firefox?

[jdkbph]

Hi. Just wondering if everyone else using Firefox 5 is seeing the same thing on the SubSim front page?

Here's what it looks like in FF5:





And here's what it looks like in IE9





Note the misalignment between the left navigation frame and the main frame in FF5.

I tried disabling all add-ons and that didn't work, so now I'm wondering if there's something wrong with FF5 in general.

Thanks

JD