well, in theory that cpu may work (might need s BIOS update). It is a AM3 cpu. AM2+ sockets support some AM3 cpus (940pins vs 941). However, it might be easier to upgrade your motherboard (as well as the cpu), you could get some newer features for a reasonable price. (ie. DDR3, faster RAM, etc.)
However, another thing that you need to take into account - is the power supply. Do you know what wattage (model?) your supply has?