I want to try to add the CallerInfo Service.
The lookup to the Ldap server can be done for all phones of the user (mobile, other phones, other mobiles, etc), as we did for corparate directory?
Yes it most certainly can. I have a highly advanced version of this application that does LDAP, Exchange and Internet lookup requests.
Hopefully your corporate directory is jsp based so you have inhouse knowledge on how to extend te ldap lookup classes in the SDK.