mh-signature-separator-flag

mh-signature-separator-flag is a variable defined in `mh-e.el'.
Its value is

t

Documentation:
*Non-nil means a signature separator should be inserted.

It is not recommended that you change this option since various
mail user agents, including MH-E, use the separator to present
the signature differently, and to suppress the signature when
replying or yanking a letter into a draft.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 8.0 of the MH-E package that is part of Emacs 22.1.