I cannot conclude this as an issue / improvement. The JAMES server does not recognize many kind of attachments when creating a MimeMessage object. This includes
1. Nested multipart contents,
2. multipart/alternative types.
3. RFC encoded headers for file names. Like continuation, base64 encoded etc
4. Inline attachments, and proprietary types like the applcation/tnef etc.
Currently , we cannot depend blindly on the Mail.getMessage(), instead we have to build the DOM Tree using MessageBuilder and parse through it.
Can this be solved?