WP_Rewrite for Multilanguage Blog

Hi, in first i want say that i’m not need a plugin like wpml or something like that…

In second: sorry for my bad English :p

ok, so, i want a multilanguage blog.. I have no problem about structuring it, my problem is in the url rewriting…

How i can do a url like as:

http://www.myblog.name/de/
http://www.myblog.name/it/
http://www.myblog.name/en/

if the query var is
index.php?lang=it or index.php?lang=de ecc.. ?