Hi, I found a working workaround for this issue. My configuration is as follows:

SW Config:
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 - Thinderbird 1.5 (version 1.5 (20060226)) = nightly build for MacOSX
- Yamb 0.6.6 (only one "Notify" is checked in imap section)
- I'm using seconds as "Account settings"

Accounts:
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- Imap server with check enevry 10 sec.
- Several folders and sub-foldes at server side.
- Using the procmail to sort e-mails on serverr side.

Before:
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- Yamb only notify when e-mail arrives in "Inbox" folder.
- It could also notify in a folder/sub-folder if you have current focus on it.

Workaround:
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Install the "Sync on Arrival" v.1.3 TB extention => no additional configuration is required.

Keep in mind that you need to enable "Offline use" for every IMAP folder.

Hope this will help out.

Dim