I dont know about sending but there certainly exists software for RECIEVING to a IR port. However, I remember there being some techincal reason why you couldn't do it with integrated laptop IR ports in NT based OS's. Something to do with Windows locking down the port or something.
Also, From certain sources, a Palm uses roughly 10% of its power just keeping the IR port active and can only beam ~ 50 cm. I would not like to see the power consumption figures for an Ipaq that can beam ~ 2m since power consumption follows a square law.