diff --git a/bindings/perl/Makefile.PL b/bindings/perl/Makefile.PL
index 34ade057..53e1028a 100644
--- a/bindings/perl/Makefile.PL
+++ b/bindings/perl/Makefile.PL
@@ -1,10 +1,34 @@
 use ExtUtils::MakeMaker;
 
 use Config;
+use File::Copy 'cp';
 use lib qw(lib);
 use Sigar::ArchName ();
 
-my $installdir = $ARGV[0] || "../../sigar-bin";
+my $installdir;
+if ($ARGV[0]) {
+    $installdir = $ARGV[0];
+}
+else {
+    #check binary-dist location and svn source location
+    for (qw(../../sigar-bin ../java/sigar-bin)) {
+        if (-e $_) {
+            $installdir = $_;
+            last;
+        }
+    }
+}
+
+my $generated_xs = "Sigar_generated.xs";
+my $build_xs = "../java/build/src/$generated_xs";
+if (-e $build_xs) {
+    #XXX should be done in the generated Makefile
+    if ((stat $generated_xs)[9] < (stat $build_xs)[9]) {
+        print "Updating $generated_xs from $build_xs\n";
+        cp $build_xs, $generated_xs;
+    }
+}
+
 my $archname = Sigar::ArchName->get_name();
 
 my $ccname = $Config{ccname};