rmail-mime-feature

rmail-mime-feature is a variable defined in `rmail.el'.
Its value is

rmailmm

Documentation:
Feature to require for MIME support in Rmail.
When starting Rmail, if `rmail-enable-mime' is non-nil, this
feature is loaded with `require'. The default value is `rmailmm'.

The library should set the variable `rmail-show-mime-function'
to an appropriate value, and optionally also set
`rmail-search-mime-message-function',
`rmail-search-mime-header-function',
`rmail-insert-mime-forwarded-message-function', and
`rmail-insert-mime-resent-message-function'.