Yes there is. While there is no user interface in 7.1.3 that will allow you to update the LDAP query, there is a table in the database that you can modify via AXL. I wrote a blog about it here:
http://www.netcraftsmen.net/resources/blogs/axl-sql-toolkit-part-3-updating-cucm-dirsync-ldap-filter-by-example.html
It is part of a blog series and you may want to read the first two parts as well.
Note that in 8.0, the ability to modify the LDAP query via a standard UI is available.
HTH.
Regards,
Bill