can't send mail as local user

[Curt]

I've set up three email accounts in alpine (on debian Lenny.)

I can access all my inboxes (imap protocol) and send email using the
gmail smtp server (for my gmail account) and my isp's smtp server for
one account, but not the other (primary inbox account, the sole user on
my machine, i.e. curty-- see headers). When I try send
mail from this account, I get the following message:

Mail not sent: Error : need MAIL command

as if Alpine were looking for sendmail, which it shouldn't because I've
set my "SMTP Server (for sending)" variable to my ISP's smtp server (for
gmail, I use a role).

Anyway, this is puzzling. My secondary email account with my ISP works
normally. I'm not running an mta (I had nullmailer set up but
deleted it thinking it might be the source of my problem).

Anyway, any thoughts?

Thank you.