It's failed in deleting instance from GUI and RuntimeException was thrown out.
STEP1: Create a cluster , then create instance on cluster.
STEP2: Delete the instance from GUI "Clusters -> %NAME of the cluster% -> Instance".
In STEP2, The message like "An error has occurred java.lang.RuntimeException:" was thrown out to the GUI, and the instance can not be deleted.
2 gf's trunk until 2012/09/12