Jason Wahler has been doing great since "Celebrity Rehab" -- he's been clean since the show ended and he's even working at a rehab facility. But we're about to rain on his parade ...

As TMZ first reported, Wahler
was sued by his ex publicity firm for allegedly stiffing them on the bill.
This week in Beverly Hills, a judge passed down a judgment ordering Wahler to fork over $3,210.
Making amends to your publicist is a step you just can't skip.
"Celebrity Rehab" star
Jason Wahler just got slapped with a lawsuit for allegedly owing money to the one person in Hollywood an actor should always pay and never piss off ... his publicist.

According to docs filed this week in LA County small claims court,
P3R Publicity claims Wahler breached a contract by failing to make payments to the tune of $5,000.
P3R tells us, "Considering Jason Wahler's track record, P3R is disappointed but not entirely shocked by his lack of honor and irresponsible behavior." They added, "Perhaps his next reality show should be VH1's "Charm School.'"
Calls to Wahler were not immediately returned.

Good news:
Jason Wahler was not busted for DUI last night.
Bad news: He was busted for assault.
Law enforcement sources tell TMZ they were called to a party in Hollywood early this morning after a girl, not Wahler's girlfriend, complained the former "
Hills" star struck her after an argument.
Wahler was arrested and booked for misdemeanor battery.

It should be easier than finding oil in the Gulf ... but "
Celebrity Rehab" has been put on ice because they just can't find a big star with a big problem.
Sources connected with the show tell TMZ producers of "Celeb Rehab" can't fill the roster for the new season, which was supposed to start shooting today.
As we first reported,
Tila Tequila and
Jason Wahler signed on, but there are still holes in the roster. Most important ... we're told there isn't a big headliner.
Our sources say producers offered
Lindsay Lohan $1 million and her own show, but LiLo turned them down. We're thinking a good move on Lindsay's part.
Scroll down for more sobering news ...
TMZ has learned Celebrity Rehab is all set to add another star to its cast -- "
Bone Thugs-N-Harmony" rapper
Bizzy Bone.

We're told Bizzy - real name
Byron McCane -- wants to seek treatment for an addiction to marijuana and alcohol.
As we've previously reported, the producers behind the VH1reality show starring
Dr. Drew have been on a mission to lock down a cast -- and fast ... or else the show could be in danger.
If the show survives -- Bizzy could join
Tila Tequila and
Jason Wahler inside the rehab facility.
TMZ has learned the people behind "
Celebrity Rehab" are closing in on another cast member for the show -- former "
Laguna Beach" star
Jason Wahler.

Wahler certainly has the prerequisites for the show -- he's been arrested several times in alcohol-related incidents .. like
this,
this,
this,
this, and
this.
We're told no deal has been signed yet -- but the two sides are getting very close to an agreement.
As TMZ first reported, the VH1 show starring
Dr. Drew Pinsky has already locked up
Tila Tequila -- but they're still scrambling to fill the rest of the cast.
Jason Wahler is going for an all-time international party boy record. The former "
Hills" star just got charged with two counts of DUI after his second alcohol-related arrest in a month.
According to the Orange County District Attorney, Wahler -- whose blood alcohol level was allegedly .15% when he was busted on March 19 -- faces six months in jail if convicted.
Just a week earlier, Wahler was arrested after a
bar fight in Cabo San Lucas, Mexico -- then mysteriously bailed out and traveled back across the border to start more trouble.
Jason Wahler was arrested last night -- in the United States for a change -- for allegedly driving under the influence.
Newport Beach PD tells us Wahler was popped last night around 10:54 PM. He was driving a 2008 Chevy Tahoe and described himself to police as "an actor."
He was released this morning under his own recognizance.
As you may recall, Wahler was arrested in Cabo San Lucas, Mexico earlier this month
after a bar fight.
Jason Wahler -- former star of "
The Hills" and "
Laguna Beach" -- has somehow made his way out of a Mexican jail, but for some reason the
U.S. Consulate is keeping the reason for Jason's release a secret.

Wahler was cuffed in
Cabo last Thursday and thrown in the pokey after getting in a fight. We couldn't find any record of Jason yesterday when we called various jails.
Today the Consulate told TMZ Jason was released seven hours after being locked up. As for why jailers let him out: Wahler signed a document keeping the terms of his release secret. We've never heard of that either.
Jason's dad tells TMZ as far as he knows no charges were filed against his son and he's back in L.A. His dad says Jason tells him he was not drinking and was actually released after one hour.
"
Laguna Beach" pseudo-star
Jason Wahler got a serious dose of reality Thursday night -- because dude was cuffed and thrown into the back of a pickup truck in Mexico after he allegedly got into a fight at a nightclub.

Sources tell TMZ it all went down at the
Pink Kitty nightclub in Cabo San Lucas where Wahler allegedly got into a scuffle with someone inside the bar.
We're told security escorted Wahler outside after the alleged fight where cops manhandled him and tossed him into the back of a pickup truck.
The local police told us they didn't have anybody named Jason Wahler in their jail ... and so far no comments from his rep or lawyer ... so ... if you we never see him again, we know why.

Former "
Laguna Beach" star
Jason Wahler got beach-slapped by the law Friday night after Laguna Beach cops say he got drunk and threw his shoes at people ... seriously.
According to law enforcement sources, Wahler got into a scuffle with a bouncer at the
Ocean Avenue Brewery and eventually got himself ejected.
Somehow Wahler made his way back inside, cops said, and the bouncers had to toss him out again.
But here's the best part: Witnesses say a frustrated Wahler then removed his shoes and fired them into the bar -- and when security came out to remove him permanently, Jason allegedly threw a punch.
Cops soon arrived on scene and arrested the reality reject for battery and public intoxication.
Wahler still had 11 days left on his probation stemming from a drunken, racist, homophobic, violent tirade back in 2007-- which means he's gonna get in even more trouble if convicted.