Cant send Mails. Postfix ?

[jens@f2h9.de]

Hi,

I cant send Mails.
When i try to send a Mail. IMP says :
"There was an error sending your message"

in /var/log/mail is :
Jul 14 23:56:33 rudi4 popper[18018]: @localhost: -ERR Too few arguments for
the auth command.
Jul 14 23:56:34 rudi4 postfix[18020]: fatal: must be run by the superuser, not
by userid 30
Jul 14 23:56:35 rudi4 postfix[18021]: fatal: must be run by the superuser, not
by userid 30
Jul 14 23:56:36 rudi4 popper[18018]: Stats: jens 0 0 34 282516
Jul 14 23:56:37 rudi4 popper[18023]: @localhost: -ERR Too few arguments for
the auth command.
Jul 14 23:56:37 rudi4 popper[18023]: Stats: jens 0 0 34 282516

Does anyone have an idea ?

Jens