How to add shell backend?

[Jung Joowon <jwjung@camis.kaist.ac.kr>]

Hello...

I have used UM slapd to convert LDAP search to Sybase SQL.
The code was implemented as shell backend using Sybase CT-library.

I want to change UM slapd to OpenLDAP 1.1.2. But, I could not find
how to use shell backend in OpenLDAP.

Would you let me know how to do it or give some pointers?

-Jung Joowon