Comment 11 for bug 294991

Well... it's not entirely fixed.

Let's put it this way: if you have *only* the SIP account enabled, then the SIP account is still pre-selected in the account selection list (when you add a contact). The "Add contact" is even smart enough to add the prefix sip: and the @server.net suffix when you finished typing the phone number ;).

If you have multiple accounts (and at least one of them supports the "Add Contact") then, indeed, it's not possible to select the SIP account.