mutt fails to send

[Alexander Harizanov]

Hi all,
I have mutt under debian lenny. I configured it to work with my gmail account. 
When I tried to send email it failed with message "msmtp: envelope from 
harizanov.alexan...@gmail.com not accepted by the server msmtp: server message 
530.5.5.1 authentication required"
There is no problem with receiving messages from gmail through fetchmail and 
mutt.
Any ideas how to fix this ?