It was never released - but the song was picked up by Louis Walsh, Girls Aloud's manager.
Girls Aloud then put their vocals over the top, while keeping the same backing track and backing vocals.
According to the Sun newspaper, record company Polydor have admitted that Orchid's backing vocals are still there on the chorus - but not so much they needed to be credited.
After all, it is common for session singers to sing on bits of records.
But the real fuss is because Girls Aloud have been having a go at One True Voice for releasing a cover.
They claim theirs is a true original - but now it appears it's not as original as we thought.
Orchid - a London girl band - are said to be so upset about someone else having a hit with their song that they've split up.
And the controversy doesn't appear to have hurt Girls Aloud.
The girl band, created by the TV show Popstars: The Rivals, are confident they'll be the Christmas Number One when the new chart is unveiled on Sunday.