[boost] [ASIO] Having a hard time after upgrading my boost libraries

Folks, I recently moved to boost 1.52, been using a pretty old version of boost earlier. Quite a number of pieces of my code have stopped working since then, but the one that's really a pain is the ASIO piece. I have a lot of code that makes use of ASIO's async read/write and other calls and there seems to be a problem reading data from socket with async_read_until - sometimes I get empty string, there's valid data at other times. My code is heavily multi-threaded. This problem doesn't show up in single threaded environment at all. My OS is SUSE 11 and g++-4.3.3 as the compiler. I may have to post some code eventually but on the top off your head - do you have any pointers for me? Thanks for your time. Arpan