just for completeness sake, if you need to find out what the privileges names are you can do this (after succesfully connecting to an esx host as a user with the administrator role):
use Data::Dumper;
my $host_view = Vim::find_entity_view(view_type => 'HostSystem');
my $content = Vim::get_service_content();
my $authMgr = Vim::get_view(mo_ref => $content->authorizationManager);
my $rolelist = $authMgr->roleList;
print Dumper $rolelist;
This might save you some frustration time 