#118826 ** 'p4 change' has a new '-u' option to allow the owner of a submitted change to update its description and/or jobs fields. (Bug #1159).
but because of this bug, which has been fixed in 2008.1 and later releases,
#149573 ** 'p4 change -u' no longer requires both the username and workspace of the user to match those of the owner of the submitted change. Now only the username needs to match. (Bug #25380, #28412)
you might also need to use the -c and -H flags as a workaround in 2007.2.
There’s not built-in action for the Perforce ‘change’ command, you’ll need to use the Perforce generic action to update the change list. I don’t have a copy of Perforce installed on this machine but the action parameters should be something like: