Ok I have to say after searching..........I am just not sure but maybe. There are a bunch of submodels and it will only work with some of them.
Found this hopefully it will help: http://forum.notebookreview.com/lenovo-ibm/206675-penryn-available-t61-t61p-64-88-motherboard.html
If you have one of those models I think you are ok. You might contact Lenovo directly and make sure though. Sorry I could not help more. Maybe try reposting this in the laptop section of the forums.