Cannot checkout or update from svnserve 1.6

Hi guys,

I have the TortoiseSVN build of the command line client, built against
r1451811. I'm trying to update an upgraded 1.7 working copy from a
repository served by svnserve 1.6.11

Update from the repo root works OK, update from lower down in the tree
fails with:

svn up
Updating '.':
svn: E210001: Unknown command 'get-iprops'

I thought it might be a problem with the WC upgrade so I tried a fresh
checkout and got the same error.

Server is running on Windows SBS 2003
Client is running on Windows 7
If you need access to the test repo I used I can give it via PM.

Simon

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