50 Cent Bans Ciara From Collaborating With Birdman / Lil' Wayne

50 Cent (real name Curtis Jackson) has apparently banned Ciara from collaborating with Birdman and Lil' Wayne, after a dispute.

The feud is between 50's G-Unit and Cash Money Records, after G-Unit rapper Young Buck signed with Cash Money.

In retaliation, Jackson has now asked r&b star Ciara not to collaborate with Cash Money founder Bryan "Birdman" Williams.

A source close to G-Unit says, "Nobody affiliated with 50 Cent can be affiliated with his enemy."