I have recently finished coding a site using, PHP, XHTML, CSS and a little javascript. The problem is that when i view the site index.php and, the browser has problems showing all the contents.

There are three different things that have happened.
1: the site is loaded all fine
2: the site is loaded all fine, then the content part (included with php) disappears (after having been shown for a short time)
3: the content part doesn't appear at all

The odd thing is that if you view the code, the content part is there. (Starts after <div id="tekst">, line 45)

I have tested with several browsers and it has happened with all of them. the (not so good) solution to the problem is refreshing the site untill all the contents have appeared

if you wish to check out what i mean, the address to the site is

although i must warn you, the contents is in norwegian.

my best guess is that the error has to do with some css/cache problems.
but the css does validate as correct so it must have to do with some weird browser incompability problem...