Need some postfix/procmail help

I have tried to implement procmail using the Jason Derleau article on macdevcenter.com. Unfortunately I am not having much success. As a postfix/procmail neophite, I did find something that raises a question in my mind. In the Cyrus 'deliver' command, as defined in 'master.cf', the '-m' arguement has '${extension} ${user}'. However, in the 'procmailrc' file, Jason's Cyrus 'deliver' command '-m' argument has 'user/$USER'. Why is this argument not '$EXTENSION $USER'? I'm hoping this is the problem. No mail is getting through when I use Jason's configurations. I don't know where I can find any logs for this but the system.log does have an 'auxpropfunc error -1' in it. I don't know if this it related to my problme or not. I would be grateful to anyone who can point me in the right direction. TIA.