... Apparently thunderbird has a bug that doesn't allow you to chose smtp servers for each email address - it defaults to the top one on the list.
I am not sure of what you are speaking.

I have multiple e-mail accounts ( albeit with the same ISP ) that are managed through Thunderbird ( on some of the computers I use: on some I use Seamonkey, a derivative of Thunderbird for the e-mail. )

My Default Outgoing SMTP Server is for the main account, but I can set up different outgoing servers ( based on user name ) for each account. I just scroll to the bottom of the “Mail and Newsgroups Account Settings” to “Outgoing Server (SMTP)” and add or edit for the individual accounts ( now reviewing Seamonkey settings, but I believe it is the same for the parent Thunderbird, as I have them set up the same way. )

Is this what you are referring to?

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