Paul: Check out PageMaster/ex 2000 at http://www.omnitrend.com/Exchange/PageMasterEX2000.html
This is a text messaging connector for Exchange that supports pagers and cell phones (SMS). If you are running Exchange 5.5, there is a version for that as well. Joe Urso List Charter and FAQ at: http://www.sunbelt-software.com/exchange_list_charter.htm