Rock singer Kurt Cobain (1967 - 1994) performs on stage with Nirvana at the MTV Video Music Awards in September 1992. (Frank Micelotta/Getty Images)

The surviving members of the grunge rock group Nirvana are angry about how the late Kurt Cobain's avatar can be used in the latest version of the Guitar Hero video game.

Courtney Love, Cobain's widow has also complained on Twitter about her husband's inclusion in the game. She said that she never approved Cobain's digital likeness for the game and said he would have despised the game and his avatar.

"While we were aware of Kurt's image being used with two Nirvana songs, we didn't know players have the ability to unlock the character," Krist Novoselic and Dave Grohl, former Nirvana members said in a joint statement on Thursday.

Unlocking the character means that users can make the character play songs by other artists.

Novoselic and Grohl said they were dismayed and very disappointed when they found out that Cobain's avatar could be unlocked.

"This feature allows the character to be used with any kind of song the player wants. We urge Activision to do the right thing in 're-locking' Kurt's character so that this won't continue in the future," said Novoselic and Grohl.

Meanwhile Guitar Hero's publisher Activision said in a statement on Thursday that they got all of the necessary legal rights with Love's signature on an agreement allowing them to license Cobain's likeness for a fully playable character in Guitar Hero 5.

The 85 tracks in the latest version of the game include Nirvana songs Smells Like Teen Spirit and Lithium.

"This is the first time the original recording of Smells Like Teen Spirit has ever been licensed in an entertainment property and we're thrilled to offer Guitar Hero fans exclusive access to the unreleased live version of Lithium," said Tim Riley, vice-president of music affairs for Activision.

Another 25 artists from a variety of music genres will also be making their music video game debut, said a statement from Activision.

Carlos Santana and Johnny Cash are among the other real-life musicians featured in the latest edition of Guitar Hero.

The likenesses of Jimi Hendrix, Billy Corgan, Ted Nugent, Sting, Ozzy Osbourne, Travis Barker and members of Aerosmith have appeared in previous editions of the game.

Nirvana formed in 1986 and in 1991 signed to Geffen records. That same year they produced their second album Nevermind which featured the hit singles Smells Like Teen Spirit, Come as You Are, and Lithium.

Cobain died from an apparently self-inflicted gunshot wound at his Seattle home in April 1994.