Having tried to recreate the index, after four hours this process has crashed too.

/usr/lib/ruby/gems/1.8/gems/lockfile-1.4.3/lib/lockfile.rb:364:in `unlock': /home/fred/.sup/lock (Lockfile::StolenLockError)

from /usr/lib/ruby/gems/1.8/gems/sup-0.12/lib/sup/index.rb:87:in `unlock'

from /usr/lib/ruby/gems/1.8/gems/sup-0.12/bin/sup-sync:206

from /usr/bin/sup-sync:19:in `load'

from /usr/bin/sup-sync:19

 

That's it for me I think.  Maybe I'll try Sup again after it's been through a few more versions.