Bizzare one-way networking prob

Hey all, just joined the forums to maybe find some advice for our strange problem here.

We've got 2 macs set up identically, 10.5.6

Mac1 can connect to Mac2 with zero problems. Browse, copy files, etc.

Mac 2 can see Mac1 but when I try to connect, it waits 30 seconds and says Connection Failed.

I set them up exactly the same... is there some obvious trick I'm missing? Thanks in advance!

There are two places in System Preferences that you want to make sure are identical. Security and Sharing. Verify that everything is identical in both of these categories...