mac address/ terminal comand ?

[graphiteG4]

yesterday i found myself in the situation were i needed to temporarily change my mac address for network purposes but when i went to terminal to enter the command ifconfig en0 lladdr (new mac address) i got an a message saying
ifconfig: ioctl (set lladdr)peration not permitted.


is this not the right command for the job or is there a setting that may have been turned on to disable this.

notes
in admin
operating system mac osx version 10.5.6

any help would be appreciated

thank you

 

[Jethryn Freyman]

try:

sudo ifconfig en0 ether xx:xx:xx:xx:xx:xx