[HLUG] How to setup multiple pop/smtp account??

[Emon]

Hi all

I am a newbie running Slackware10.2 with KDE desktop.

I am using mozilla-thunderbird-1.0.6 to check my mails.

I have two pop/smtp accounts

1) mail_emon at gawab.com

2) contact_emon at gawab.com

The first account is the default account.

I have configured mozilla-thunderbird to use different folders for each 
of the account.

I can receive mails from both accounts without any problems.

I can send mail with the default account but not the second account!

While sending mails from the second account, it tries to log into 
smtp.gawab.com with the username "mail at gawab.com" & asks for the 
password; & after receiving the password it complains...

***************
An error occurred while sending mail. The mail server responded: You are 
trying to send an email from address other than yours (#5.7.1). Please 
verify that your email address is correct in your Mail preferences and 
try again.
***************

Although I am non-technical person, but I thought if it could log into 
smtp.gawab.com with the username "contact_emon at gawab.com" maybe the 
problem will be solved... so I went to "Edit -> Account Settings -> 
Outgoing server(SMTP) -> Advanced" and added another outgoing smpt 
server with all the previous options but with the user name 
"contact_emon at gawab.com"; but all in vain :(.....

It is still trying to log into smtp.gawab.com with the username 
"mail at gawab.com" & giving me the same error.....

Is there a way out or am I stuck with one account??

Thanks
Emon

BTW: I had to change my "default account" & "default smpt" to be able to 
send this mail using this(contact_emon at gawab.com) account.