added some protections in case of connecting to class signals (in case class does not exist).
added some protections in case of connecting to class signals (in case
class does not exist).


git-svn-id: ecbadac9c76e8cf640a0bca86f6bd796c98521e3@821 27541ba8-7e3a-0410-8455-c3a389f83636

bbannier/ROOT,dawehner/root,dawehner/root,dawehner/root,dawehner/root,bbannier/ROOT,bbannier/ROOT,bbannier/ROOT,dawehner/root,bbannier/ROOT,bbannier/ROOT,dawehner/root,dawehner/root,bbannier/ROOT,dawehner/root