So this has been sitting around for a bit: http://hackage.haskell.org/trac/ghc/ticket/2391 And I'm sort of hoping we can get it resolved soon so that a fixed version is included in GHC 6.10. My basic thoughts are: 1. Listening on both IPV4 and IPV6, if I recall correctly, introduces all sorts of interesting problems, and basically, you don't want to go there. Or am I wrong about that? 2. We should default to IPv4 if someone uses the current interface, as that's what most people will be expecting, as that's the Linux (and probably Windows) behvaiour. 3. Given this, we should add a separate "PortNumber6 Int" value constructor that informs listenOn to use IPv6 instead of IPv4, so that people can use IPv6 with the simple interface. Thoughts? cjs -- Curt Sampson <cjs@starling-software.com> +81 90 7737 2974 Mobile sites and software consulting: http://www.starling-software.com