Sienna Miller and Sadie Frost are reportedly feuding over Jude Law - again.

Sadie, the actor's ex-wife, is said to be furious the pair have rekindled their romance and allegedly told the Alfie star, in an email, that Sienna would never make him happy.

A source told Britain's Grazia magazine: "Sadie said he was mad to go back to Sienna. She said he really changes when he is with her, he becomes stressed and emotionally all over the place."

Jude reportedly showed the email rant to Sienna who was incensed.

The 'Layer Cake' actress sent an angry email back to Sadie accusing her of being jealous and unable to accept that her ex was moving on.

Sadie allegedly responded by phoning Jude and telling him she would not be a shoulder for him to cry on anymore.

The source added: "Sadie called Jude and screamed 'I'm not going to be there to nurse your wounds when she drives you mad - and it will happen'." (Bang Showbiz)