I don't think any of the so-far released transcript points towards suicide. The first alarm goes off while both pilots are in the cockpit, and they 'start to try and diagnose the problem,' according to what I've heard. The alarm precedes anything else. Then the autopilot is disconnected. Until the beginning of the emergency they were 'chatting like pals'. That the co-pilot should pray and say 'I put my fate in your hands' is quite in line with the oriental/islamic tradition of fatalism, ie, belief that your destiny resides with a higher power (which is ultimately true, even if that 'higher power' is just chaos and circumstance). I'm not suggesting someone definitely DIDN'T flip out and commit suicide/murder, but I just haven't seen any evidence of it. When the co-pilot said he was "going into death", all he was really doing was stating the facts as they were at the time.
When faced with certain impending doom, pilots say different things, inevitably heartbreaking. Saying goodbye to spouses, it's horrible. The crew of the Turkish Airlines DC10 that crashed outside Paris after a UA232-alike loss of controls were singing a tune from a Turkish breakfast cereal all the way down (once the plane went out of control), and I can think of other equally chilling things. A Surinam DC8 crashed when the non-ATPL rated copilot (who was in his 70s) made a complete mess of a raw-data approach. About five seconds before impact the flight engineer realised the futility of the situation and said, "That's it, I'm dead." No less spooky than "I put my fate in your hands" and "going into death".
I know it's an unpleasant thing to dwell on but people do all kinds of strange things when suddenly placed in extreme danger, and it's very easy to read things into it. My friend who had the misfortune to be first officer on a 707 that lost engines 3 & 4 and a fair amount of the right wing over the Alps watched in horror as the Icelandic (ie not a fatalistic Muslim, for those of you who think such behaviour is restricted to Arabs and the like) captain folded his arms and said, "We're all going to die now." In this case they survived (the tower could see them before they broke out of the clouds because of the 200 ft trail of fire from the wing tanks) and in both cases the cause of the crashes was quickly discovered. But "I put my fate in your hands" is no more or less sinister than "I love you Amy" (USAir at Pittsburgh) or "Shit" (the last word on about 90% of CVRs). In fact "I put my fate in your hands" is a more spiritual way of exiting the planet than "shit" or whatever, more the sound of a spiritually enlightened person accepting that their fate is no longer in their control, rather than any sign of suicidal intent.
Remember the master alarm went off first, and we are far from being in possession of all the facts. I must say the plot thickens at every turn but with each development we are no nearer to finding the cause of this tragedy.
fly Saha Air 707s daily from Tehran's downtown Mehrabad to Mashhad, Kish Island and Ahwaz