Napster announced Tuesday it will lean on music catalog specialist Gracenote to help it weed out copyright music. Berkeley-based Gracenote catalogs music for online information access and software applications.

Gracenote also catalogs the spelling variants that have proved troublesome for Napster as the song-swap service tries to comply with a federal court injunction to block the trading ofunauthorized content. Gracenote’s database of song titles, including misspellings, is about 12million and is based on user submissions.

“We’ve been exploring a partnership with Gracenote for months and the ability to quickly enlist their support in our file-filtering efforts will greatly improve our effectiveness,” Napster CEO Hank Barry said in a statement. “We are leaving no stone unturned in our efforts to comply with the court’s injunction.”

Gracenote normally provides its services as an added feature to desktop music playing software such as MusicMatch and Winamp, popping up artist and song titles on PCs when users insert an audio CD.

“Our core business is really not helping peer-to-peer networks filter. But it was just a perfect fit,” Gracenote president David Hyman said.

Although terms of the deal between the two online companies were not revealed, Hymanconfirmed that Napster will have full access to Gracenote’s database of music information.

“Personally, I feel like it’s a great moment in digital music,” Hyman said. “It’s part of thesolution that keeps the Napster phenomenon alive.”

Napster has struggled to comply with an injunction that requires it to block access to certain songs after receiving proper notice from the copyright holders. The Recording IndustryAssociation of America, on behalf of its members, submitted 135,000 filenames to Napster March 9 to have them blocked from the file-sharing service.

But Napster’s efforts have been slowed somewhat by the large number of misspellings and variants on song and artist names. Some Napster users even have resorted to Pig Latin to sneak their favorite tunes onto the service.

Spelling variants of artists’ names – “MMetallica” or “etallicaMay,” for instance – have lessened the effectiveness of Napster’s week-old screening technology, the company said.