Time stamp in html-helper-mode

[Mik]

I was using html-helper-mode with Emacs 20.13.50.2 to make web-pages,
and found that
the time stamp ("Last modified") between the hhmts tags was
automatically updated when
the file was saved.   I have now upgraded to 22.3.1, but find the
feature no longer works.
I checked that the variable html-helper-do-write-file-hooks is set to
"t".  Anyone know what
is wrong?

I was running the older Emacs on a Mac G4 (OS X 10.3) but am now on a
Mac INTEL
with OS  X 10.5, but I wouldn't think that platform should make a
difference.