Same here
Sorry for a 'me too' post but....
Leopard, whilst I like it in many ways, has been a disaster for networking AFAIC. GPRS data via my Nokia E61 no longer works and it does something that crashes my D-Link DSL-604+ router. I now rely on wireless at work and university and dialup into Windows 2000 inside VMWare with Nokia's PCSuite - at home only my XP machine and old Acorn RISC PC are able to use the ADSL and only if there's no mac connected.
Cheers,
Daniel.