this is what I typed, looking in help it appears to be correct.
netdom renamecomputer kpc309 /newname:kal-lo-wrk-009 /userd:gary /password:thisisit /reboot:10
also tried
netdom renamecomputer kpc309.spock.com /newname:kal-lo-wrk-009.spock.com /userd:gary /password:thisisit /reboot:10
also tried
netdom renamecomputer kpc309.spock.com /newname:kal-lo-wrk-009.spock.com /userd:spock\gary /password:thisisit /reboot:10
everything points me to netdom help, which looks exactly like what I typed