yea the code posted wasnt the whole code, theres also a sidebar and that was screwing things up.. i made dozens of wordpress sites and didnt encounter this before so thats why i didnt post it.
Anyway, i put a 1px dot, line height 0px, in the first div like this:
<div id="main"><p class="smalldot">.</p><div id="content"><div id="insidecontent">
and this somehow aligns all divs and texts the right way. Thanks for your efforts peeps.