undoing ifconfig plumb?

[Ken Hawkins]

is this possible? i have a box that is unreachable now after I had ran 
ifconfig em0 plumb command.

I am in the midst of setting up a box that has multiple ip's on a 
single ethernet connection with differing subnet masks however, in the 
midst i got botted off the box (ssh kick) and BANG cannot  get back in!

ssh: connect to host web1.prosoundweb.com port 22: No route to host

I need to undo my screw up here. can anyone help out?

thanks,
ken;