I have a strange behaviour with e-mail addresses having dot. Presumably Ext plugin has a typo in inet-address parsing in ListProvider.

Case 1:
Project Recipient List: adonai.elohim, cc:master.maker, bcc:lich.king
In this case Ext plugin only sends E-mail to adonai.elohim$suffix
CC and BCC are ignored

Case 2:
Project Recipient List: adonai.elohim, cc:"master.maker", bcc:lich.king
In this case Ext plugin sends E-mail to adonai.elohim$suffix
and CC's to "master.maker"$suffix,
BCC is ignored
(btw I see these quotes around names when reading with mail-client)

Case 3:
Project Recipient List: adonai.elohim, cc:"master.maker", bcc:"lich.king"
In this case Ext plugin sends E-mail to adonai.elohim$suffix
and CC's to "master.maker"$suffix and "lich.king"$suffix,
no BCC is sent, all recipients are visible