Paris Responsible For Rihanna/Chris Brown Blowout?!?

That's what OK! Magazine is suggesting at least! Ugh, Paris, I hope this isn't true.

First of all, a source tells the mag that - on the Thursday before Grammy weekend - Chris and Rihanna "were in a non-stop argument." Why? He wanted to drive to the Grammys in a sports car and she wanted a bigger car so her friends could tag along. He won out, but "they were late for rehearsals and she was infuriated."

And now for the Paris deets! On Friday at the Verizon & BlackBerry Storm Grammy bash at Boulevard 3, Rihanna performed... and that's when Chris "chatted up Paris Hilton." Hates it!

A witness explains: "He and Paris went outside together," and later on in the night "Paris was all over him. Rihanna caught wind of it and spent the rest of the night glued to him."

Hmm, what to think of all this! Was it just an innocent flirtation that made Rihanna needlessly jealous or did Chris (and Paris) take things too far? Is this report even true?