Looks like 3Com is not one of the supported products, link:
http://www.aol.co.uk/products/broadb...omoCode=228937
But, hopefully, someone here, or via this link:
http://www.adslguide.org.uk/qanda.asp?faq=DSLHardware
Will be able to advise you further, and get both your computers up and running at same time, I did it when I was on AOL, but used the netgear WG834G and matching card bought from the DSLwharehouse:
http://www.dsl-warehouse.co.uk/default.asp
good luck