Can't access network

I just got my Intel iMac and I want to move files over from my old PowerPC iMac on my network. Everything is connected, file sharing is turned on, etc. The old Mac shows up just fine, however, I cannot connect to it. If I click on the icon under "Shared", it says the connection failed. If I click on "Connect As..." I get a dialog box that says the same thing.

I can connect to the new Mac from the old one just fine. I also noticed that when I turn on Screen Sharing on the old Mac, the link shows up immediately on the new computer. Of course, it won't connect.

I've run Disk Repair and Repair Disk Permissions. The latter reports issues but from what I read, that may not matter.

I've read that it isn't the best idea to use Migration Assistant to move stuff over from a PowerPC to Intel Mac and I'd really rather not use a jump drive or CD to move everything by hand. Using a network always worked for me before.

Any ideas?