Swedish letters are shown as squares on the site with IE

[frankw]

Hi

I am using vbulletin on my swedish forum, everything was working well untill now when I saw that all my swedish letters arent shown correctly the first time i enter the forum when using Internet Explorer

they are shown as small squaresfigures instead of letters.

if i click anywhere on the site the problem is fixed but the first impression of the site gets ruined because of this.

how could this have happend? is this something common with non-english characters thats easy to fix?