If 'svn merge' tries to add a symbolic link, you get an ordinary file instead:
[sussman@BenBook:~/scratch]$ svnadmin create repos
[sussman@BenBook:~/scratch]$ svn co file://`pwd`/repos wc
Checked out revision 0.
[sussman@BenBook:~/scratch]$ cd wc
[sussman@BenBook:~/scratch/wc]$ svn mkdir trunk
A trunk
[sussman@BenBook:~/scratch/wc]$ svn mkdir branch
A branch
[sussman@BenBook:~/scratch/wc]$ svn ci -m "r1"
Adding branch
Adding trunk
Committed revision 1.
[sussman@BenBook:~/scratch/wc]$ svn up
At revision 1.
[sussman@BenBook:~/scratch/wc]$ cd branch
[sussman@BenBook:~/scratch/wc/branch]$ touch foo
[sussman@BenBook:~/scratch/wc/branch]$ svn add foo
A foo
[sussman@BenBook:~/scratch/wc/branch]$ ln -s link foo
ln: foo: File exists
[sussman@BenBook:~/scratch/wc/branch]$ ln -s foo link
[sussman@BenBook:~/scratch/wc/branch]$ svn add link
A link
[sussman@BenBook:~/scratch/wc/branch]$ svn st
A foo
A link
[sussman@BenBook:~/scratch/wc/branch]$ ll
total 8
-rw-r--r-- 1 sussman sussman 0 30 Sep 14:33 foo
lrwxr-xr-x 1 sussman sussman 3 30 Sep 14:33 link@ -> foo
[sussman@BenBook:~/scratch/wc/branch]$ svn ci -m "r2"
Adding branch/foo
Adding branch/link
Transmitting file data ..
Committed revision 2.
[sussman@BenBook:~/scratch/wc/branch]$ cd ..
[sussman@BenBook:~/scratch/wc]$ cd trunk/
[sussman@BenBook:~/scratch/wc/trunk]$ svn merge -r1:2 file:///Users/sussman/scratch/repos/
branch
A foo
A link
[sussman@BenBook:~/scratch/wc/trunk]$ svn st
A + foo
~ + link
[sussman@BenBook:~/scratch/wc/trunk]$ ll
total 8
-rw-r--r-- 1 sussman sussman 0 30 Sep 14:34 foo
-rw-r--r-- 1 sussman sussman 8 30 Sep 14:34 link
[sussman@BenBook:~/scratch/wc/trunk]$ svn pl -v link
Properties on 'link':
svn:special : *
Very odd. The 'svn:special' property is there, but the thing ain't a symlink.