Many of the posters seem to have all the sympathy for this player - which is understandable - but I want to point out that concentrating on the story, NPC's, other players and giving COMPLETE attention to every move this players makes, frankly makes me feel stressed. I feel that I do lot of extra to help this player and since he's not the only player at the table, my brain gets jammed.
Now I feel a bit pissed off because I just noticed that his summons (which he uses lot and so far NPC's never) have casting time of 1 round, not 1 standard action. It seems that he has never bothered about this and since I don't check every single detail what the character does, I have let him cast summon monsters as 1 standard action since that is sort of the default casting time. From now this will change, but it seems that I really have to read every single spell description myself when he uses them and most of the time this will during combat. Which is so annoying YYYYYYYAAAAAARGH! I demand some sympathy too