>>************************************
>>create trigger colTeste For mt_input
>>after update as
>>begin
>>
>> update mt_output
>
>You are calling 'update' inside a trigger defined as firing AFTER an update.....

Yes, but I want to update table mt_OUTput after an update in mt_INput. Since it is not the same table, there would be no reason for a infinite loop.

>you've set up an infiniate loop that probably crashes after user resources are consumed...

Interbase doesn't even let me create the trigger.....

I have the same trigger in an Oracle Database and it works just fine.