Debugging csup for DragonFly

[walt]

FreeBSD-current has csup in the base system, and I've tried using it
twice on DF with mixed results.

The FBSD sources compile on DF without modification, and the binary
will fetch a freshly checked-out src/ from DF.

The problem is that csup will choke with a 'Protocol error' when
importing any changes from the server.  If I delete the outdated
files then csup will check out the new versions with no problem.

While trying to debug this problem I used a packet sniffer to look
at the network traffic and ran across a different puzzle:  I have
no /usr/src/kerberosIV directory, even though I can see the network
traffic talking about all the files that should be in it, and the
'checkouts' file in /usr/sup/ includes the kerberosIV directory.
Any ideas?

Is anyone here using csup successfully?  If not, how is everyone
updating sources?