UPDATE 2-Russian court acquits allofmp3.com music site owner

(Adds more quotes, appeal planned)

By James Kilner

MOSCOW, Aug 15 (Reuters) - A Russian court found the former boss of music download Web site www.allofmp3.com not guilty of breaching copyright on Wednesday in a case considered a crucial test of Russia's commitment to fighting piracy.

The allofmp3.com Web site angered Western music companies by undercutting the price of downloads in deals they said breached copyright law.

Denis Kvasov, head of MediaServices which owned the site, was put on trial after entertainment companies EMI Group Plc EMI.L, NBC Universal (GE.N: Quote, Profile, Research, Stock Buzz) and Time Warner Inc. (TWX.N: Quote, Profile, Research, Stock Buzz) pressed for a prosecution.

"The prosecution did not succeed in presenting persuasive evidence of his involvement in infringing copyright law," said judge Yekaterina Sharapova.

A local official with the International Federation of the Phonographic Industry (IFPI), which is representing copyright holders in the case, said it would appeal the decision.

"We are disappointed with the verdict and will appeal," IFPI regional director Igor Pozhitkov told reporters.

The site has been a thorny issue in negotiations between Russia and the United States over Russia's accession to the World Trade Organisation, a key aim of President Vladimir Putin.