Makefile.PL | 2 +-

diff --git a/Makefile.PL b/Makefile.PL
index 8e710df2a31379fe616b7fab18120e9592c8b5ab..57592378c76d554cda85daa343250a02f25bedb4 100644
--- a/Makefile.PL
+++ b/Makefile.PL
@@ -118,7 +118,7 @@ 	my $base = $_;
 	my $mod = $base;
 	$mod =~ s!/!::!g;
 	$mod =~ s/\.\w+\z//;
-	"lib/PublicInbox/$_" => "blib/man3/PublicInbox::$mod.3"
+	"lib/PublicInbox/$_" => "blib/man3/PublicInbox::$mod.\$(MAN3EXT)"
 } qw(Git.pm Import.pm WWW.pod SaPlugin/ListMirror.pod);
 my $warn_no_pod = @no_pod ? "\n\t\@echo W: missing .pod: @no_pod\n" : '';