[Users] Move some Claws mailboxes to Thunderbird?

[Victoria S.]

I've searched Google and tried various things suggested, with no success.

I use Claws Mail (version 3.8.0) at home, but I am restricted to Thunderbird at work - although I do have access to Evolution, if needed (this issue; not used).

I have also access to Thunderbird at home (I use it as a RSS feed client/reader) and Evolution (again, not used). 

Unfortunately, I am not able to use Claws, at work.

My home operating system is Ubuntu 12.04 LTS (and 64-bit); at work it's CentOS 6.

My Claws mail is stored under Mailbox (MH); on my home computer at ~/Mail/.

I have a Claws mail folder/directory, with 321 subfolders and thousands of messages, that I would like to be able to import into Thunderbird

How can I go about accomplishing this task?

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