unique id required

["Arpit Jain" <j.arpit@gmail.com>]

Dear List Members,

OpenLDAP version 2.3.39 on RHEL5

I am using "OpenLDAP " to store information. This information is
retrieved by a "client" and made available to "user" via the
vfs(virtual fire system) interface in linux. The user then
reads/writes/browses the information just like in a filesystem. I can
store a 64-bit id of each entry as inode number in my client.

A "unique id" of size 64-bits is required for each entry so that once
an entry is searched by giving "dn", further searches for the entry
can be done using that unique id.
The unique id must be in some way auto-generated by openldap server.

entryUUID has been identified to fulfills all the requirements except
that it is 128-bit long.

I would like to know if there is some other operational attribute
which is unique for each entry and of size 64-bits?
of if I can extract a 64-bit unique value from entryUUID or any other attribute?
If required the operation can be shifted to some other version of OpenLDAP also.

Arpit J.
Center for Development of Advanced Computing (C-DAC)
http://www.cdac.in