Originally Posted by Bored

I would need to see an example.
If you can copy/paste the CSS
www.rbpaste.com

or a sample, I would be more than happy to take a look. Sounds like a simple case where the elements are set to a specific width. 100px, and you have two elements inside that are 50px each. When a 1px border is added to one of these elements, the total is more than 100px, so the second element is forced to the next line, because it doesnt have enough room.