This kind of error message:

$ svk pull
Syncing svn+ssh://des3jjm@vega.dur.ac.uk/home/hudson/pg/des3jjm/subversion/docs
Retrieving log information from 249 to 249
    (in cleanup) Svndiff data ends unexpectedly: Unexpected end of svndiff input
Svndiff data ends unexpectedly: Unexpected end of svndiff input
    (in cleanup) Svndiff data ends unexpectedly: Unexpected end of svniff input

Can be caused by:

$ df                                                          
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/mapper/engdebian52-root
                                6890048   6560316         0 100% /

So it's really not worth re-mirroring the whole repository...

Rather than using cut and grep (to find files present locally, but not checked in):

svk status | grep "^\?" | cut -d " " -f 2

You can use awk:

svk status | awk '/^\?/ {print $2;}'

Or sed:

svk status | sed -e '/^?/!d' -e 's/^?\s*//'

Or, just for fun, perl:

svk status | perl -ne 'print $1."\n" if /^\?\s*(.*)/'