function generatehash($length=8){
	  $chars='qwertyuiopasdfghjklzxcvbnm1234567890';
	  $numshars = strlen($chars);
	  $hash = '';
	  for ($i=0; $i < $length; $i++) {
	    $hash.=substr($chars, rand(1,$numshars)-1, 1);
	  }
	  return $hash;
	}