Re: rmailmime.el

[Richard Stallman]

    Following your idea will work well for text/plan of us-ascii charset
    in 7bit transfer-encoding.  In case of quoted-printable or base64
    encoding, or non-us-ascii charsets, even if a message is text/plain,
    it should be decoded and internalized according to its designated
    charset to display it in an Emacs buffer.

In some cases it can be decoded in the current buffer.
The very simple mime-handler I use does that for quoted-printable.
For base64, by contrast, it puts the attachment text into another buffer.
I decided to do it that way because the things that are encoded in base64
are often not text at all; they are jpeg or pdf, for instance.

But if we use metamail to handle the other formats in a special way,
then text which is encoded in base64 could be decoded in the same
buffer.