array is given instead of a string

[gilgalbiblewhee]

I'm getting this error:

Warning: mb_strlen() expects parameter 1 to be string, array given in ../getBibleCodeinclude.php on line 30

function mb_str_split($str, $length = 1){
  if ($length < 1) return FALSE;
  $result = array();
  for ($i = 0; $i < mb_strlen($str); $i += $length) {
    $result[] = mb_substr($str, $i, $length);
  }
  return $result;
}
for($tdid=0; $tdid < count($id); $tdid++){
    $strText=stripslashes(mysql_escape_string($textData[$tdid]));
    include("../includefiles/vowelmarks.php");
    for($i=0; $i<count($vm); $i++){
        //echo $vm[$i];
        $strText=str_replace($vm[$i], "", $strText);
    }
    $text=str_split($strText);
    /********************************************************************************/
    //$text  = "süpérbrôsé";
$solo = mb_str_split($text);
$quintet = mb_str_split($text, 5);

print_r($solo);
print_r($quintet);
echo "end";
    /********************************************************************************/