At my homepage, I use for SSI-pages something like the following:

<!--#config timefmt="%d.%m.%y %H:%M" -->
Last modified: <!--#echo var="LAST_MODIFIED" -->
[download]

This prints something like:
Last modified: 07.11.02 01:31 Best regards,
perl -e "s>>*F>e=>y)\*martinF)stronat)=>print,print v8.8.8.32.11.32"