A321 Dispatcher is informed almost 30 minutes after the fact; by the crew; of a Probe Heat Computer failure that will require returning or diversion for repair. A diversion and overweight landing is then accomplished; where the aircraft is repaired before continuing to destination.

Narrative

Thirty minutes after takeoff I received an ACARS message from the crew 'STATUS MAX FL100/MEA WITH FO R STAT FO TAT ARE WE REALLY RESTRICTED TO 10;000 FT.' I advised the crew to standby while I confer with Maintenance. I had reviewed the QRH and the ECAM Non Normal procedures. All the information there stated First Officer (FO) stat inoperative systems - First Officer pitot; Left Stat; Right Stat; First Officer TAT - crew awareness. Nowhere in either of the manuals does it reference 10;000 FT restriction. After I told the crew to standby so I could get with Maintenance; he stated 'been talking to Local Maintenance for 20 plus minutes'. Neither I nor Maintenance Control knew anything about the situation until the crew asked about the 10;000 FT restriction. The only reference to 10;000 FT restriction was on his ECAM. The crew asked where you want us to go and where is the part. Maintenance Control advised the part was available in ZZZ. Either going back or landing ZZZ; the aircraft would be landing overweight. The flight also had a failure - no PHC 2 [Probe Heat Computer] data idcfds. Based on these facts; the safest course of action would be to land ZZZ; long runways. Did not want the flight to stay in the air any longer in the event they lost or the other side iced up. The aircraft would then have no reliable air data. Plan was made to land ZZZ approximately 8;500 LBS over maximum landing weight. Message was sent to crew to attempt to burn extra fuel on the way to ZZZ. Then only a walk around overweight landing inspection would be required. Flight landed ZZZ taxied to the gate. Captain called Dispatch and advised it was smooth landing; it was not a hard landing. Maintenance did the walk around inspection; changed the parts that failed and the flight continued to destination. Dispatch did check the flight history of down links from the aircraft. There were 2 failures and 2 warnings; takeoff minus 12 minutes - Failure Fuel Level Sensing; takeoff plus 1 - Warning anti ice First Officer TAT; takeoff +1 Warning anti ice First Officer Right STAT; takeoff +2 Failure NO PHC 2 DATA/idcfds. Once again; based on all available information; landing overweight was the safest course of action; rather than allowing the aircraft to fly for at least 2 more hours to burn the fuel off.Original cause was in part; a lack of communications from Local Maintenance and/or flight crew to Dispatch. Not knowing about a problem until 28 minutes after departure is; in my opinion; unacceptable. Local Maintenance should have advised Maintenance Control in Dispatch of the problem also. Neither was done. The reason the decision to land over weight was deemed to be the safest course of action at the time. [I] did not want to keep the aircraft in the air any longer than needed. Suggest Company Policy is changed about overweight landings. We have procedures in place for overweight landings based on manufacturer data. You cannot just simply say we will not land overweight. If the crew had been allowed to continue flying the aircraft for another 2 hours; I believe would have been a violation by allowing the flight to continue in unsafe condition.