I usually have no probs running a Mac in a mixed environment (my network has a lone Mac which I use for video/graphics and a bunch of Linux and Windows PCs). U should check to see if ur office have a proxy server, and if the program can autodetect it. Some cannot. It's usually program specific.

Oso, if ur office got active directory, see if ur mac can connect to it (I not sure about post-OS-X, but for pre-OS-X need to buy a program to allow it to join).

Good Luck!