Note: the change in subject. ;-)
Yahoo!'s firewall with no proxy option connects to Yahoo! by wrapping the YMSG protocol inside HTTP. Gaim currently doesn't support doing this.
Does libyahoo2 support it?
Why the split between the two? IMHO it would be much better to have a single free implementation of the protocol. So many different implementations with some feature here and some there is heavily self-defeating for the community.
Cheerio, Debarshi