Werk #1833: jolokia_metrics.gc: fix recently introduced exception for missing variable

Component	Checks & agents
Title	jolokia_metrics.gc: fix recently introduced exception for missing variable
Date	Jan 7, 2015
Level	Trivial Change
Class	Bug Fix
Compatibility	Compatible - no manual interaction needed
Checkmk versions & editions	1.2.7i1 Checkmk Community, Checkmk Pro, Checkmk Ultimate MT

To the list of all Werks