Before revision:  We show that in general, the c \mu rule is not stabilizing (i.e. there are stabilizable arrival and service rate parameters for which the multi-server c \mu rule results in unstable queues ) .
After revision:  We show that in general, the c \mu rule is not stabilizing (i.e. there are stabilizable arrival and service rate parameters for which the multi-server c \mu rule results in unstable queues , even for arrival rates within the capacity region .