Dragut asa cum ai reusit tu.
Eu m-am complicat:

[code]
for($i=0;$i<count($users)+1;$i++){
    for($j=$i+1;$j<count($users);$j++){
        if($users[$i]['name'] == $users[$j]['name']){
            for($k=0;$k<count($users[$i]['ip']+$users[$j]['ip']);$k++){
                for($l=0;$l<count($users[$i]['ip']+$users[$j]['ip']);$l++)
                    if($users[$i]['ip'][$k] == $users[$j]['ip'][$l]){
                        unset($users[$j]['ip'][$l]);
                    }
            }
            for($l=0;$l<count($users[$j]['ip']);$l++)
                $users[$i]['ip'][] = $users[$j]['ip'][$l+1];
            unset($users[$j]);
            $users = array_values($users);
        }
    }
}
[/code]