SVN externals (externals failed, already locked)

Hi,

I've been expermenting with SVN externals and found an issue which i
dont fully understand. My repository is as follows;

------------------

+Play (with and extern to URL "https://swserver:8443/svn/Play/Shared
Sources" Local Path "Project 3")

- Project 3 (externed)
-> shared.txt

- Project 2 (with an extern to URL
"https://swserver:8443/svn/Play/Shared Sources" Local Path "Outstation
Files")
-> -> Outstation Files (externed)
-> -> -> shared.txt
-> -> unieque.txt

-> Project 1 (with an extern to URL
"https://swserver:8443/svn/Play/Shared Sources" Local Path "osfiles")
-> -> osfiles (externed)
-> -> -> shared.txt
-> -> unieque.txt

- Shared Sources
-> shared.txt

---------------------

All the externs work as expected and changes to files in "Shared
Sources" are reflected across the 3 projects. However when doing an
update/checkout i get the following error " 'External failed Project 3'
is allready locked via ."

I suspect that its because i am external'ing not into a seperate folder,
whereas in "Project 1" and "Project 2" the "Shared Sources" go in there
own folder. However the externals do work as expected.

I am using subversion 1.7.4 (same on server), via TortoiseSVN.

regards

---
Matthew J Fletcher
amimjf(at)sky.com
www.amimjf.org
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