ok, so i got the answer from victoriaann through mail, here it goes:
” a computer genius friend of mine seemed to be able to fix it by removing clear:right from div#primary so it reads div#primary{}
The change had no effect in firefox or chrome, but fixed it in IE7 (or IE8 quirks mode)
for myself, i found a different approach which is the following:
add change the #wrapper to text-align: right
remove the float: right from #sidebar
add text-align : left; to both #wrapper and #sidebar
it works fine on IE7, firefox & so .. and you get rid of one float which is not bad thing itself.