suggestion on web-based contact manager

[Gianluca Bosco <g.bosco@bitache.net>]

Can anyone suggest me a good web-based contact manager, which can handle 
 private address books? Basically I would like my users to be able to 
manage their own personal address book through some sort of web interface.

I have browsed the archives - and had a look at ldap-abook and rolodap. 
Actually, such projects seem to be not actively maintained and I would 
like to know about some other alternatives.

TIA,

-Gian