recursive loop...

<psuedo-code>

sub rename_dir {
  $curdir = shift;
  opendir($curdir)
  foreach $dir(readdir($curdir)) {
    next unless $dir is directory; 
    &rename_dir($dir); # recurse
    rename($dir);
  }
  closedir(current dir)
}
[download]

</psuedo-code>
something to that effect should work, i can't create a test run here, but i think the basics should be in that example..
basically this follows the dir tree to the end, and then rename directories as it comes out of the loop.
-Syn0