None too pretty, but here's one that gets the job done at 58:

sub rle {
  my$c;map{shift;$c++;$_[0]ne$_?do{$a="$_*$c";$c=0;$a}:()}@_
}
[download]

Though, it has some "issues"...

   MeowChow                                   
               s aamecha.s a..a\u$&owag.print