The ipv6 line was strange but I read a while back, some tech note about ensuring that is your last line in hosts.
Perhaps IPv6 is enabled. I had a few instances where I turned it off during install, but found it enabled at runtime. I had assumed I was being careless during install... but perhaps this a bug.
Check the interface using ifconfig to see what it's status is.
In terms of tools for debugging, I would use strace/truss after using the -v switch to ssh. Strace and truss will show you what system functions are being called during application runtime (by the ssh client, in this case).
-geoff
--------------------------------- Geoff Galitz Blankenheim NRW, Germany http://www.galitz.org/ http://german-way.com/blog/