diff --git a/plugins/openvpn/openvpn_multi b/plugins/openvpn/openvpn_multi
index ce2b60c3..3bc05918 100755
--- a/plugins/openvpn/openvpn_multi
+++ b/plugins/openvpn/openvpn_multi
@@ -1,89 +1,178 @@
-#!/bin/sh
-#
-# Plugin Configuration
-#  [openvpn_multi]
-#   user root
-#   env.statusfile /var/log/openvpn.status
-#   env.userlist user1 user2 ...
-#
-#
-# No error handling/mapping for ${userlist} => ${statusfile}
-#
-# Magic markers (optional - used by munin-config and some installation
-# scripts):
-#
-#%# family=auto
-#%# capabilities=autoconf suggest
+#!/usr/bin/perl -w
 
-if [ "$1" = "autoconf" ]; then
-	if [ -f ${statusfile} ]; then
-		echo yes
-		exit 0
-	else
-		echo "no (${statusfile} not found)"
-		exit 1
-	fi
-fi
+=head1 NAME
 
-if [ "$1" = "suggest" ]; then
-	echo "Configure a status file..."
-	exit 0
-fi
+openvpn_multi - Plugin for monitoring OpenVPN users traffic
 
-FieldAttrib () {
-	echo "${USER}_in.label ${USER} Received"
-	echo "${USER}_in.type DERIVE"
-	echo "${USER}_in.min 0"
-	echo "${USER}_in.graph no"
-	echo "${USER}_in.cdef ${USER}_in,1,*"
-	echo "${USER}_out.label ${USER} Bps"
-	echo "${USER}_out.type DERIVE"
-	echo "${USER}_out.min 0"
-	echo "${USER}_out.negative ${USER}_in"
-	echo "${USER}_out.cdef ${USER}_out,1,*"
+=head1 USAGE
+
+Standard plugin
+
+=head1 AUTHOR
+
+Copyright 2013 Pierre Schweitzer <pierre@reactos.org>
+
+=head1 LICENSE
+
+GNU GPL v2 or any later version
+
+=head1 MAGIC MARKERS
+
+ #%# family=auto
+ #%# capabilities=autoconf
+
+=cut
+
+use strict;
+use Munin::Common::Defaults;
+use Munin::Plugin;
+
+my $statusfile = ($ENV{'statusfile'} || '/var/log/openvpn.status');
+
+sub config {
+	open FILE, $statusfile or die $!;
+
+	print "multigraph openvpn_users\n";
+	print "graph_title OpenVPN traffic\n";
+	print "graph_args --base 1024 --lower-limit 0\n";
+	print "graph_vlabel Bytes Out (-) / In (+) per \${graph_period}\n";
+	print "graph_category openvpn\n";
+	print "in.label recv\n";
+	print "in.type DERIVE\n";
+	print "in.min 0\n";
+	print "in.graph no\n";
+	print "in.cdef in,1,*\n";
+	print "out.label Bps\n";
+	print "out.type DERIVE\n";
+	print "out.min 0\n";
+	print "out.negative in\n";
+	print "out.cdef out,1,*\n";
+
+	while (<FILE>) {
+		next if ($_ =~ /CLIENT LIST/ || $_ =~ /Updated/ || $_ =~ /Common Name/);
+		last if ($_ =~ /ROUTING TABLE/);
+
+		# client,IP:port,in,out,D M N hour Y
+		my @values = split(',', $_);
+		my $name = $values[0];
+		my $fieldname = clean_fieldname($name);
+
+		print "multigraph openvpn_users.$fieldname\n";
+		print "graph_title OpenVPN traffic for $name\n";
+		print "graph_args --base 1024 --lower-limit 0\n";
+		print "graph_vlabel Bytes Out (-) / In (+) per \${graph_period}\n";
+		print "graph_category openvpn\n";
+		print "in.label recv\n";
+		print "in.type DERIVE\n";
+		print "in.min 0\n";
+		print "in.graph no\n";
+		print "in.cdef in,1,*\n";
+		print "out.label Bps\n";
+		print "out.type DERIVE\n";
+		print "out.min 0\n";
+		print "out.negative in\n";
+		print "out.cdef out,1,*\n";
+	}
+	close FILE;
+
+	exit 0;
 }
 
-GetValues () {
-	if grep -q ^$USER $statusfile; then
-		awk -F , '/^'"$USER"'/ {print $1"_in.value "$3 "\n"$1"_out.value "$4}' $statusfile
-	else
-		echo "${USER}_in.value -1"
-		echo "${USER}_out.value -1"
-	fi
+sub autoconf {
+	if (-e $statusfile) {
+		print "yes\n";
+		exit 0;
+	} else {
+		print "no\n";
+		exit 1;
+	}
 }
 
+sub report {
+	my %in;
+	my %out;
+	my $tot_in = 0;
+	my $tot_out = 0;
 
-# Setup config
-if [ "$1" = "config" ]; then
-        echo "graph_title Root Graph of Openvpn Traffic by CN"
-        echo "graph_args --base 1024 --lower-limit 0"
-        echo "graph_vlabel Bytes Out (-) / In (+) per \${graph_period}"
-	echo "graph_category openvpn"
-	echo "graph_info This graph shows the bandwidth usage in Bytes/s. It prepulates the graph lines from a list of user CN's in the plugin conf file, this must correlate with the values in the ${statusfile} log file."
-        for USER in $userlist
-        do
-		FieldAttrib
-        done
-        for USER in $userlist
-        do
-		echo "multigraph openvpn_multi.${USER}"
-        	echo "graph_title ${USER} sub-graph"
-		echo "graph_category openvpn"
-		echo "graph_info This graph shows the bandwidth usage in bytes/s. It prepulates the graph lines from a list of user CN's in the plugin conf file, this must correlate with the values in the ${statusfile} log file."
-		FieldAttrib
-	done
-	exit 0
-fi;
+	my %previous_state = restore_state();
+	my %new_state;
 
-# Get .values for root graph
-for USER in $userlist
-do
-	GetValues
-done
+	open FILE, $statusfile or die $!;
+	while (<FILE>) {
+		next if ($_ =~ /CLIENT LIST/ || $_ =~ /Updated/ || $_ =~ /Common Name/);
+		last if ($_ =~ /ROUTING TABLE/);
 
-# Get .values for sub-graphs
-for USER in $userlist
-do
-	echo "multigraph openvpn_multi.${USER}"
-	GetValues
-done
+		# client,IP:port,in,out,D M N hour Y
+		my @values = split(',', $_);
+		my $name = $values[0];
+
+		my $in = 0;
+		my $out = 0;
+		if (exists $previous_state{$name."_in"} && exists $previous_state{$name."_out"}) {
+			my $old_in = $previous_state{$name."_in"};
+			my $old_out = $previous_state{$name."_out"};
+			if ($old_in <= $values[2] && $old_out <= $values[3]) {
+				$in = $values[2] - $old_in;
+				$out = $values[3] - $old_out;
+			}
+		}
+
+		$in{$name} = $in;
+		$out{$name} = $out;
+		$tot_in += $in;
+		$tot_out += $out;
+
+		$new_state{$name."_in"} = $values[2];
+		$new_state{$name."_out"} = $values[3];
+	}
+	close FILE;
+
+	print "multigraph openvpn_users\n";
+	if (exists $previous_state{"total.in"} && exists $previous_state{"total.out"}) {
+		my $old_tot_in = $previous_state{"total.in"};
+		my $old_tot_out = $previous_state{"total.out"};
+		if ($old_tot_in <= $tot_in && $old_tot_out <= $tot_out) {
+			print "in.value $tot_in\n";
+			print "out.value $tot_out\n";
+		} else {
+			print "in.value 0\n";
+			print "out.value 0\n";
+		}
+	}  else {
+		print "in.value 0\n";
+		print "out.value 0\n";
+	}
+
+	$new_state{"total.in"} = $tot_in;
+	$new_state{"total.out"} = $tot_out;
+
+	save_state(%new_state);
+
+	for my $name (keys %in) {
+		my $in = $in{$name};
+		my $out = $out{$name};
+		my $fieldname = clean_fieldname($name);
+
+		print "multigraph openvpn_users.$fieldname\n";
+		print "in.value $in\n";
+		print "out.value $out\n";
+	}
+
+	exit 0;
+}
+
+if ($ARGV[0]) {
+	my $arg = $ARGV[0];
+	my %funcs = (
+		config   => \&config,
+		autoconf => \&autoconf,
+	);
+
+	if (exists $funcs{$arg}) {
+		$funcs{$arg}->();
+	} else {
+		die "Unknown argument '$arg'\n";
+	}
+} else {
+	report();
+}