Small Soldiers tells the story of intelligent and vicious warring toy soldiers

"We see this as a little guy against the big guy case," Mr Grant's lawyer Ira Reiner told trade magazine Variety.

"It is highly unlikely that a jury will conclude anything other than that there was copying here."

But the studios involved all deny lifting the idea.

The attorney representing all three companies, Bert Fields, said the fact that Mr Grant's ex-wife had signed a copyright licence as co-author meant the action would be defeated.

But Mr Grant is aiming to show his ex-wife did not have any creative input in the short film.

According to the legal action, Ode to GI Joe appeared in several film festivals in 1991.

The film also won a student award from the Academy of Motion Picture Arts and Sciences.

Hi-tech battle

Amblin, Spielberg's production company, does not dispute receiving the film but contends Small Soldiers was based on a script by Gavin Scott.

According to Variety, the defendants see Mr Grant's suit as an attempt to claim ownership of the generic theme of toy soldiers coming to life.

The case is not expected to be heard until 2002.

Small Soldiers centres around the son of a toy store owner who tries out some new hi-tech action figures: The Commando Elite and the Gorgonites.

Unfortunately, both sets of toys have been designed with computer chips to move, talk and destroy each other.

A battle ensues, in which the full destructive ability of creative computer chips fighting one another is revealed - with surprising results.