Thanks for your replies.
By looking at RFC4533 AND slapo-accesslog I __don't__ think they can be used against what my contributed overlay can do.
The overlay actually monitors add/delete/modify operations based on attributes/dn/classobject and if they matches it triggers event to the URL (like interrupt).
Now the thing is: in our case, the web-page is not used to display modifications to users or on the browser __rather__ it perform some operations on other enterprise applications based on the event triggered from LDAP overlay hence polling kind of mechanism can't work for us.
We are going to use this overlay in our open-source-product "Zivios - Open Source Enterprise Management". Zivios will be used for management of all enterprise applications (like OpenLDAP, Kerberos, Mail-Server, Network Time Server etc) from a single web-based panel, so all modifications done through Zivios on LDAP will be made/reflected on other applications/servers at the same time. Now if somebody perform some operation on OpenLDAP directly (means by skipping Zivios) then Zivios should be triggered for such a change and then it can act on other servers accordingly. Thus event received by Zivios is __not__ for displaying data; rather its for doing some background processing although this overlay can be used to display LDAP operations on web too.
Please suggest me someother way which can work on scenario mentioned above if my overlay isn't good enough. Let me know if overlay name or description isn't clear and is creating misundestanding about the functionality of the overlay.