catalytic converter replacement

I do Smog for a living in California and I have seen quite a few later model Corolla's with CAT problems. I think that Toyota needs to step up and stand behind their defective Catalytic Converters in the later Corollas. I have had to replace several and the customer has to pay a LOT of money. I really do not think that it is fair or right. I wish I had a better answer because the State requires a new factory CAT because the after market CATs are not qualified for replacement in the whole State of CA. I really think that their should be a recall but as of this week, and I just spoke to Toyota, there is none.