Index: t3lib/utility/class.t3lib_utility_client.php
===================================================================
--- t3lib/utility/class.t3lib_utility_client.php	(revision 7850)
+++ t3lib/utility/class.t3lib_utility_client.php	(working copy)
@@ -89,9 +89,15 @@
 					$browserInfo['all'][$matches['browser'][$i]] = $matches['version'][$i];
 				}
 			}
+				//Replace gecko build date with version given by rv
+			if (isset($browserInfo['all']['gecko'])) {
+				preg_match_all('/rv:([0-9\.]*)/', strtolower($userAgent), $version);
+				if ($version[1][0]) {
+					$browserInfo['all']['gecko'] = $version[1][0];
+				}
+			}
 		}
 
-
 		// system
 		$browserInfo['system'] = '';
 		if (strstr($userAgent, 'Win')) {