I'm a little unclear of what you are talking about when you say "coolant block". Did you blow a freeze plug in the engine block? Are you talking about the coolant pipe that fits into the side of the engine block?
http://www.realoem.com/bmw/showparts...67&hg=11&fg=35 (it's the pipe looking thing between #'s 6 and 7 in the diagram)
If so, that is not an uncommon failure on ti's, especially those with high mileage. Regardless of whether it is that pipe or not, I guess my next question would be: How hot did it get before you noticed it and if it was already pretty hot by the time you did, did you also blow the head gasket and/or did you warp/crack the cylinder head?
If you can post pictures of what busted or where the water is coming from, that would be helpful.