BREAKIN' ALL THE RULES — * 1/2 — Jamie Foxx, Gabrielle Union, Morris Chestnut; rated PG-13 (vulgarity, profanity, brief sex, violence, brief drugs, racial epithets, nude artwork).

It's ironic that a film called "Breakin' All the Rules" doesn't really break any.

Instead, it's a disturbingly conventional and painfully cliched bore that doesn't violate any existing cinematic rules, except maybe that romantic comedies are supposed to be funny.

There's nothing to distinguish this virtually laughless, tedious mess from any number of formulaic television sitcoms, aside from the fact that it's been padded out to feature length (under 90 minutes, though it feels longer).

Jamie Foxx stars as Quincy, an L.A.-based magazine staff writer, but he makes a less-than-endearing leading man. When Quincy's would-be fiance (Bianca Lawson) dumps him, she heads to Paris.

Meanwhile, Quincy's new cost-cutting boss (Peter MacNicol) has basically forced Quincy to become his new hatchet-man. When he's not firing other magazine staffers, Quincy uses unsent but bitter letters to his ex as the basis for what becomes a best-selling instructional manual on relationship break-ups.

At the same time, Quincy's cousin, Evan (Morris Chestnut), decides to try the book's strategies on his girlfriend Nicky (Gabrielle Union), whom he is trying to beat to the punch. As a result, she winds up in the arms of Quincy.

Essentially, the film's plot is little more than a series of misunderstandings and miscommunications, none of which are as amusing as screenwriter/director Daniel Taplitz intends. And the outcome of each subplot is painfully obvious.

Foxx's on-screen double-dealing alter-ego isn't all that likable, and Chestnut's womanizer character is only slightly more appealing. In fact, you may find yourself rooting for Union's character to wash her hands of both of them.

"Breakin' All the Rules" is rated PG-13 for crude humor (references to and jokes about bodily and sexual functions of humans and animals), scattered use of strong profanity and racial epithets, some brief sexual contact, violence (fisticuffs, mostly overheard), brief references to drug use, and a close-up on some nude artwork. Running time: 86 minutes.