I'm not seeing these problems that you've described. Have you made some changes to the site since you posted this? Also, I don't notice any issues in FF 3, but in IE 7 your middle column doesn't fully reach the top of the page.
I have a few problems I have discovered, I am coding for a friend, a free job.
1) The right column isn't completely reaching the top's alignment. (I will give my source code validation links below. The xhtml one I can't figure out because I do not see a problem with it, I have used it before the same code and it works).
2) The CSS class; navWrap, when I was coding it I made a mistake and added a "p" after the { so like, navWrap {p, I tried to remove it but it fucks with the whoel template layout, all the columns get overlapped and centered in the template, the the login box on the right gets pushed under the navbar and floated to the left.
Error Screenshots (This is the result of removing the p from outside the navwrap bracket.)
--- http://i44.tinypic.com/300bi1j.jpg http://i43.tinypic.com/2qaqlwo.jpg
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3) All of this I would like to do without a negative margin, I know its possible it is just not working.