Google adsense rejection

I'm trying to make adsense work on my second blog, named, but I keep getting rejected.

I have asked in a google group and was told that my server issues the wrong header, what ever that means.

Do you know have to solve the problem, and make my site available to google's bots.



Ps: This is the top of the header:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "">
<html xmlns="" dir="ltr" lang="da-DK">
<head profile="">
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />