A 
Expression which can be used to split a 
MailMessage
 per attachment. For example if a mail message has 5 attachments, then this
 expression will return a 
List<Message> that contains 5 
Message.
 The message is split:
 
   
     | As a byte[] or String | The attachments are split into new messages as the body. This allows the split messages to be easily used by
       other processors / routes, as many other camel components can work on the byte[] or String, e.g. it can be written to disk
       using camel-file. | 
 
 In both cases the attachment name is written to a the camel header "CamelSplitAttachmentId"