The ad you can hear on TV at Oskar's home, is real. No changes or corrections have been made. This was a real commercial of the NPD (German ultra-conservative and racial party) shown during the 2003 election
The german title "Wochenende fuer Inlaenderfreunde" isn't quite the same as the aka-title "Weekend for racists". It means the same, but "Inländerfreunde" is a non-existing stupid word Micha makes up, because he doesn't dare to say that he's a racist. During the Election 2005 in Germany, the NPD (German ultra-conservative and racial party) hung posters calling themselves "inländerfreundlich". This happened half a year after the film was officially released
While bored, Micha and Steven start watching a very strange sock-fetish video tape on TV. This film isn't made by the creators of "Weekend for racists", it really exists and can be bought through the Internet
Every time a new character appears on screen, you can see a poster of a politician in the background: Edmund Stoiber (CSU, German conservative party) is shown behind Micha and Steven. Holger Apfel (NPD,German ultra-conservative and racial party) is shown behind Oskar. Lothar Bisky (PDS, German radical left-wing party) is shown behind the old women, who watches TV.
Gregor Erler is not only Steven (baldy), he also has a brief appearance as the homeless guitar player (long hair, beard). The close-ups of the guitar player were shot in advance, so Gregor Erler could shave his head. When Steven beats up the guitar player a double was used.