Just kidding... Slow, Dial-up, get it? (-:{
Ok, so in 90% of all dial up speed problems, it's an old modem driver that's not allowing you to connect at speed. Usually the connection speed is 26.4 though, not 36... Check the modem settings to make sure it's not set at a max speed of 36000 baud. Also, update the drivers from US Robotics.
Last, here's what I've heard from phone companies in the past, which may be the cause... Phone companies only guarantee voice-quality service, not 56k service. If you know it's not the modem (can they dial into your Earthlink account at 56k?), then it's most likely the lines then. Check the modem on the server as well. Ignore the guys above, too. There's no conspiracy...