diff --git a/html/includes/graphs/common.inc.php b/html/includes/graphs/common.inc.php
index 31f4d9e12..d2e27f00e 100644
--- a/html/includes/graphs/common.inc.php
+++ b/html/includes/graphs/common.inc.php
@@ -7,9 +7,9 @@ if($config['trim_tobias']) { $width+=12; }
 if ($_GET['height'])  { $height = mres($_GET['height']); }
 if ($_GET['inverse']) { $in = 'out'; $out = 'in'; $inverse=TRUE; } else { $in = 'in'; $out = 'out'; }
 if ($_GET['legend'] == "no")  { $rrd_options .= " -g"; }
-if ($_GET['nototal']) { $nototal=TRUE;} else { $nototal=FALSE;}
-if ($_GET['nodetails']) { $nodetails=TRUE; } else { $nodetails=FALSE; }
-if ($_GET['noagg']) { $noagg=TRUE; } else { $noagg=FALSE; }
+if (empty($_GET['nototal'])) { $nototal=TRUE; } else { $nototal=FALSE; }
+if (empty($_GET['nodetails'])) { $nodetails=TRUE; } else { $nodetails=FALSE; }
+if (empty($_GET['noagg'])) { $noagg=TRUE; } else { $noagg=FALSE; }
 
 if ($_GET['title'] == "yes")  { $rrd_options .= " --title='".$graph_title."' "; }
 if (isset($_GET['graph_title']))  { $rrd_options .= " --title='".$_GET['graph_title']."' "; }
diff --git a/includes/rrdtool.inc.php b/includes/rrdtool.inc.php
index 7938eaf80..d1562ac68 100644
--- a/includes/rrdtool.inc.php
+++ b/includes/rrdtool.inc.php
@@ -257,6 +257,7 @@ function rrdtool_lastupdate($filename, $options)
 function rrdtool_escape($string, $maxlength = NULL)
 {
   $result = shorten_interface_type($string);
+  $result = str_replace('%','%%',$result);
   if ( is_numeric($maxlength) ) {
     $extra  = substr_count($string,':',0,$maxlength);
     $result = substr(str_pad($result, $maxlength),0,$maxlength+$extra);