Additional RSS channel information not passed through in node_feed

In attempting to write a module that allows the addition of RSS information, that will be displayed through the node_feed, I ran into a problem with the channel information not being passed through to format_rss_channel.

This is especially difficult given that iTunes information cannot be passed using the standard hook_nodeapi with media information..

The problem lines is

  $output .= format_rss_channel($channel['title'], $channel['link'], $channel['description'], $items, $channel['language']);

By simply changing the format_rss_channel to include channel information that is not part of the default, it is possible to allow for the iTunes metadata to be placed within the RSS stream.

  $output .= format_rss_channel($channel['title'], $channel['link'], $channel['description'], $items, $channel['language'], array_diff_key($channel, $channel_defaults));

Normally I'd do up a patch for this, but it's a simple change to one line that can easily be looked over. If it is required as a patch, I'll provide that. I think this is something that could potentially be back-ported, and forward-ported.