So far MAN3PODS is useless or buggy on activeperl's HTML system. Changing the parameters UpdateHTML_blib is possible and suggested in the docs for AP's MM, but I think thats very prone to future breakage. I think I will try to just have a makefile section automatically copy and rename the .xs file to a .pod. I will update this post with my results.

    MAN3PODS            => { 'MYXSLIB.xs' => '/blib/man3/MYXSLIB.3'},
[download]

# --- MakeMaker manifypods section:

POD2MAN_EXE = $(PERLRUN) "-MExtUtils::Command::MM" -e pod2man "--"
POD2MAN = $(POD2MAN_EXE)


manifypods : pure_all  \
    MYXSLIB.xs
    $(NOECHO) $(POD2MAN) --section=3 --perm_rw=$(PERM_RW) \
      MYXSLIB.xs /blib/man3/MYXSLIB.3 




# --- MakeMaker htmlifypods section:

POD2HTML_EXE = $(PERLRUN) "-MActivePerl::DocTools" -e "UpdateHTML_blib
+(installdirs => "$(INSTALLDIRS)")"
POD2HTML = $(POD2HTML_EXE)


htmlifypods :  \
    MYXSLIB.xs
    $(NOECHO) $(POD2HTML)
[download]

Update:

I found putting this in makefile.pl works with ActivePerl.

package MY;

sub postamble {
return '

MoreDocs.pod ::
    $(CP) $(BASEEXT).xs .\lib\$(FULLEXT)\MoreDocs.pod

$(BASEEXT).xs :: MoreDocs.pod


';
}
[download]