class Mail::Message

def bcc=( val )

mail.bcc #=> ['mikel@test.lindsaar.net', 'ada@test.lindsaar.net']
mail.bcc = 'Mikel , ada@test.lindsaar.net'
mail.bcc #=> ['mikel@test.lindsaar.net']
mail.bcc = 'Mikel '

Example:

Sets the Bcc value of the mail object, pass in a string of the field
def bcc=( val )
  header[:bcc] = val
end