mml-boundary-function

mml-boundary-function is a variable defined in `mml.el'.
Its value is

mml-make-boundary

• This variable may be risky if used as a file-local variable.

Documentation:
A function called to suggest a boundary.
The function may be called several times, and should try to make a new
suggestion each time. The function is called with one parameter,
which is a number that says how many times the function has been
called for this message.