Modified to support the rename of mutex to appender_list_mutex.
Modified to support the rename of mutex to appender_list_mutex.

hunter-packages/log4cplus,ccpaging/log4cplus,ccpaging/log4cplus,hunter-packages/log4cplus,ccpaging/log4cplus,hunter-packages/log4cplus,ccpaging/log4cplus,csuideal/log4cplus,csuideal/log4cplus,csuideal/log4cplus,csuideal/log4cplus,hunter-packages/log4cplus