Running ZCM 11sp1a on Suse11sp1 64 bit.

I need to uninstall/reinstall the agent on a Linux 11sp1 server. When
installing the agent I get a message back saying the agent is already
installed. If I run "zac reg -g https://zenserver.domain" I get an "Unknown
error while communicating with ZENworks Management Daemon"

So, two question ... How do I remove the Zen agent and using the "zac reg"
command how would I re-register any workstation agent to a new zone?