posting failes: Invalid Sender:-header

Hanspeter Roth <[email protected]> Sun, 14 Aug 2005 21:20:04 +0200

Newsgroups	gmane.network.tin.user
Message-ID	<[email protected]>

Hello,

in ~/.tin/tinrc I have

[email protected] (Hanspeter Roth)

When I try to post there comes a menu:

q=quit, e=edit, i=ispell, M=menu, p=post, o=postpone

When I hit the p-key there appears an error message for a few
seconds:

Invalid  Sender:-header Idefix <[email protected]>

NNTPSERVER is localhost which is leafnode.
I'm using rtin.

How can I successfully post in rtin?

-Hanspeter