Changes the permissions with which the currently-executing verb is running to be those of <player>. If <player> is not of type OBJ, then E_INVARG is raised. If the programmer is neither <player> nor a wizard, then E_PERM is raised.
Note: This does not change the owner of the currently-running verb, only the permissions of this particular invocation. It is used in verbs owned by wizards to make themselves run with lesser (usually non-wizard) permissions.