As in quite a few 'free, Western' countries, Etisalat (or probably more accurately, the Dubai CID) have a program (Echelon?) that can monitor many phone conversations at once (and I assume, emails) and pick up key words (like 'b*mb, Isr*el etc). Once picked up, it latches on to that conversation and tapes it or future conversations on that number.
As I said, this is not peculiar to the UAE. Victorian police (Australia) quite recently prosecuted a man after 'accidentally' stumbling upon telephone converstions between him and his mistress planning to murder his wife, apparently in graphic detail. I think we could safely assume the Vic. police surveillance program automatically latched on to a succession of pre-programmed inappropriate words and alerted the humans to listen in to future conversations. I believe the man received a relatively hefty gaol sentence.