I've been using Chicken of the VNC on a G4 laptop to control a Mac Mini that I use headless as a music server. It has worked great until yesterday

I could control the Mini even before I logged in to it, using Chicken to log in as the admin user. But I just upgraded the Mini to OS X 10.4.7 and now is not discoverable by Chicken on the laptop until I log in to the Mini, which sorta negates using Chicken because I don't want to have a monitor and keyboard connected to it. Right now I have to have those connected to the Mini. Once I log in Chicken sees the Mini and I can enter the password and control it.
Is there a setting in the OS to configure it this way? I have remote desktop enabled, I'm even using OSXVNC server. I need to be able to use Chicken to log in on the Mini.
Help!

Thanks.