According to Intel the max safe temp for this processor is 74.1*C. I'm not sure whether this means the processor can't work at temps above this - I think some people have posted on various forums and threads that they have achieved 70*C - 80*C (with different softwares) with stock coolers etc.
I wonder if you have the same hardware as of Feb 2012, considering the date your comment was posted.
P.S. I have the same processor. I'm trying to do a bit of overclocking too. At the moment I've only tweaked the base frequency from 266.67 MHz to 300 MHz. Everything seems to work fine with stock coolers etc. Although I need to test my system using the stress tests and softwares. Looking forward to sharing some experience with you. Hope the advice was helpful !