[texhax] Double hyphen in Emacs LaTeX mode

[Dan]

Dear All,

Is there any particular reason why, since a distro upgrade, when I
type a double hyphen -- in Emacs LaTeX mode, I now get a double quote
followed by an equals sign "= , please?  Typing a third consecutive
hyphen gets me back to having a double hyphen.  In other Emacs modes
(text, Gnuplot), typing a double hyphen produces a double hyphen as
expected.

Thanks,

Dan