HTTP_ACCEPT_LANGUAGE - Redirect usage

I have a website (www.X.com) that I have set up to support 8 languages.  Based on a query string I load up the correct languages string.  For instance:

www.X.com/about.asp?lang=fr will show French and www.X.com/about.asp?lang=de will show German

This works out great since the user can, if they need to, change langauges very quickly.

What I'd like to do, on the main page (www.X.com/default.asp) and that page only, is the first time teh page is loaded in that session, to guess what the language is and default the page to that.  

So by using Request.ServerVariables("HTTP_ACCEPT_LANGUAGE") to get the language on www.X.com/default.asp, I'd like the page to refresh and somehow work like the others.  So if a user came to default.asp and their language was FR, it would show the French page but allow them to change if necssary.  The best way I figured so far is to, on www.X.com/default.asp, to a Response.Redirect to www.X.com/default?lang=fr 

BUT I thought while surfing the net, that Yahoo! and Google frown on redirects and I don't want to get the site penalized in search rankings.

Any ideas?

Thanks,
CS