div width auto not working in FF only in IE

[FoxRocks]

Hello Everyone,

I'm a bit stumped on this problem. I've got a header which I would like to have expand the whole width of the screen regardless of screen resolution. I've set the width to auto in my css but it only works in IE not FF. I just want to start by asking if that is normal or not. I can't really post a link because the page I'm working on is actually a template for an existing photoblog script (pixelpost.org) so the only way I can get it to show online is by switching the template...and because it doesn't work and the photoblog gets a fair amount of traffic, I don't really want to leave it up. Anyways I know this is less then ideal for troubleshooting my problem but I'm thinking this is maybe just normal for FF and it might stop there. If not then I'll get something up for you.

Thanks a bunch,

~FOX~

edit: I've got it solved by using a div container for the whole header and setting it to 100%. Previously I had the header split into two separate pieces and I was trying to make the right piece auto expand which didn't work.