Why do portal users have to have a zoho account ??

Why do portal users have to have a zoho account ??

we're evaluating zoho support and it was all looking really good, but the customer support portal appears to be a show-stopper for us due to the dependence on having a zoho account.

is there any way that we can authenticate users ourselves (i.e. single sign on) ?

failing that, can strip all mention of accounts from the portal - i.e. remove the "login" link and remove the "my requests" tab ?

thanks, simon