Source url '/trunk/docs/appserver' is from different repository

I have recently converted from CVS to SVN, and while I have read the
_Version Control with Subversion_ book from cover to cover, I am still
short on real world experience with SVN.

Here is the problem that I am having:

I used the cvs2svn script to convert a CVS repository to an SVN one,
then I created a branch:

svn copy trunk branches/BP_160

The branch starts at revision 1862. On that branch, I added a new
directory tree to the repository:

svn add docs/appserver
svn commit -m 'initial revision' docs/appserver

I made a few other changes on this branch, and then decided I was ready
to merge it back to the trunk. So I did (paths and filenames changed to
protect the innocent):

: jmglov@jglover; cd trunk
: jmglov_at_jglover; svn merge -r 1862:HEAD svn+ssh://svn.mydomain.com/var/svnroot/myproject/branches/BP_160
C lib/MyProject/Global.pm
C appserver/MyProject/index.html
A docs/appserver
A docs/appserver/MyProject
A docs/appserver/MyProject/functional-specification.sxw
A docs/appserver/MyProject/technical-specification.sxw

I resolved the conflicts, then told SVN about it:

svn resolved lib/MyProject/Global.pm appserver/MyProject/index.html

Finally, I was ready to commit my trunk changes:

: jmglov@jglover; svn commit -m 'BP160: merged BP_160 branch changes 1862:1888 back into the trunk'
Adding docs/appserver
Adding docs/appserver/MyProject
Adding (bin) docs/appserver/MyProject/functional-specification.sxw
Adding (bin) docs/appserver/MyProject/technical-specification.sxw
svn: Commit failed (details follow):
svn: Source url '/trunk/docs/appserver' is from different repository

And the commit bombs out. I tried searching for this error message on
Google and only got hits on cross-referenced SVN source code, and a
search of the archives of this list were similarly unhelpful. I have
also checked "Appendix B: Troubleshooting" in the SVN book.

Can anyone shed some light on this?

TIA,
Josh

-- 
Josh Glover <josh.glover@tfcci.com>
Software Engineer
Twenty First Century Communications, Inc.
http://www.tfcci.com/
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