Is it possible for a contact to add colleagues in the Portal?

Is it possible for a contact to add colleagues in the Portal?

Hi all,

My clients wishes to enrich his database to add more Contacts to his Accounts,
Should we create a Customer Portal where the main Contact of the Account could create new contact persons? Or is there an easier way?. 

My question is whether this is supported in ZOHO Customer Portal?
Can a Portal enabled contact manipulate (add) contacts for his own Account?