minor niggle with svn completion of sub-commands

[Greg Klanderman <gak@xxxxxxxxxxxxxx>]

Can someone explain what's causing the completion of the svn
sub-command to only work when there are no words to the right of
the cursor?

For example,

% svn lo<tab>

completes to "svn log ", but

% svn lo<tab> foo

gives no completions.

I don't really understand _arguments too well, but it looks like the
use in _subversion is attempting to complete commands in the first
position.. why doesn't that always work?

thanks,
Greg