############################################################
sub split_entity {
############################################################
  local $entity = shift; # needs a MIME::Entity object
  my $num_parts = $entity->parts; # how many mime parts?

  if ($num_parts) { # we have a multipart mime message

    foreach (1..$num_parts) {
      split_entity( $entity->parts($_ - 1) );
    }

  } else { # we have a single mime message/part

    # text
    if ($entity->effective_type =~ /^text\/(?!(html|enriched))/) {
      # do something
    } else {
      # do something different
    }
  }
}