Mac to Mac dial up internet sharing

I have tried to set up my two macs, an imac SE 400 and powerbook G3 (bronze keyboard), with 10.2.4(both machines) so that they can share the same dial up internet connection.  I am using an ethernet crossover cable to connect the two machines.  I connect via dial up on my powerbook and then turn internet sharing on.  I then start my imac and turn internet sharing on and "check" the box that says "share the connection with other computers on built-in Ethernet".  So far so good.  Supposedly I should now be logging onto the network from the computer that is going to be sharing the "active" internet connection.  I now pull down the "go" file and go to "connect to server".  In the "address" section I type in the name of the computer I am trying to connect to and then press "connect".  Within 10-15 seconds I get an error message stating the name of the computer I am trying to connect to and "error - 5000.  I have tried switching the process using the opposite computers with the same results.  Just to verify the Ethernet cable is good I was able to turn file sharing on and share files between computer without any problems.
I have even gone into the Network Panes and set up a Built-In Ethernet to try and connect.  I have set up my ISP user name and password and tried to connect without any results.      Help!!!!