Reported here:
http://mail-archives.apache.org/mod_mbox/subversion-users/201205.mbox/%3CCACw0ni+z_G9oTr5vu+O=DBnjsHTyhx9x6PWVMULxPX33UKZnLg@mail.gmail.com%3E
http://svn.haxx.se/users/archive-2012-05/0156.shtml
A slightly shorter recipe:
svnadmin create repo
svn mkdir -mm file://`pwd`/repo/trunk
svn cp -mm file://`pwd`/repo/trunk ^/branch
svn co file://`pwd`/repo/branch wc
touch wc/exe
svn add wc/exe
svn ps svn:executable '*' wc/exe
svn ci -mm wc
svn sw ^/trunk wc
svn merge ^/branch wc
svn ci -mm wc
svnadmin create repo2
ln -s /bin/true repo2/hooks/pre-revprop-change
svnsync init file://`pwd`/repo2 file://`pwd`/repo/trunk
svnsync sync file://`pwd`/repo2
Now:
$ svn pg svn:executable file://`pwd`/repo/trunk/exe
*
$ svn pg svn:executable file://`pwd`/repo2/trunk/exe
$
svnsync has failed to retain the property when converting the copy into an add.