Custom validation rule + array

[eluser]sqwk[/eluser]
yes…

EDIT:
The other thing that I tested was applying a generic rule like this: (In this case the array is an additional variable)

Code:

… 'required|callback__in_array('.array("val","val2","val2").')' …

function _in_array($val, $array) {
   if (in_array($val, $array)
      return TRUE;
   else
      return FALSE;
}