It means "Go put it in your ass."

Maybe Italians are being depicted accurately in the media: Highly opinionated opera director Franco Zeffirelli held a press conference in Rome yesterday concerning his company’s new season. A reporter had the temerity to mention some of the many allegations about Italian Prime Minister Silvio Berlusconi, to which Zeffirelli responded, “You are insulting a friend a mine, a man of valor,” adding “This is a serious theater. Go away, you cretin rascal [mascalzona cretina], you asshole [stronza], go fuck off [vada a fare in culo]. You don’t belong here, how dare you! Berlusconi is a friend of mine, an extraordinary man.” Also, curse words sound much better in Italian, no?