here is a past thread with a similar issue...
Don't know what mail client you are using but you should be able to use "mail"
"Paraiso" credited for this code:
echo "This is a test" | mail -s test firstname.lastname@example.org
I use Kmail, and the string below works for me on the command line, however, It opens Kmail composition window, everything is populated correctly but I have to hit Ctrl+Return to acutally send it out.
kmail -s test --body "this is a test" email@example.com
Maybe someone could tell me How I can | pipe the Ctrl+Return to Kmail so it will send automatically.
Hope this helps.