Questions about lastmod overlay

Hi,

I want to get last modified timestamps, etc, on individual entries in OpenLDAP just as I get them in my about to be retired Netscape server. But I noticed that that lastmod overlay is not built by default when you compile from source (one needs to include the "--enable-lastmod" when running configure). And so, of course, my current binary doesn't support that function. Is there a downside to using the lastmod overlay? Can I just recompile and reinstall and not have to actually rebuild the database, or do I have to dump the database and reload it again?

Thanks, Rob