The problem with this suggestion :
The forums and the Graal Website are not on the same domain. When you log in to Graal, a "cookie" is set to tell the website you're logged in (that's a bit more complex but the idea is here).
Your browser will send the cookie only when you're browsing the graalonline website, and the forums don't get that cookie.
Before, it was possible to set a cookie from domain1.com for domain2.com but now the new IE6 cookie protection blocks it (more than 80% of visitors usually use IE6). We can't make a such big improvement only for people using older versions of IE or Opera (dunno if opera accept cross-site cookies), Mozilla (dunno too), Konkeror, Lynx, iBrowse, Miami, etc... (yup I have know lots of browsers, even Amiga ones)
And finally, this is just for the look&feel. Since we have some other, more important, things to do, this idea will not be added to our TODO list for now (later, maybe ?

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