1. A method performed by a communication device for declaring a radio link failure (RLF), comprising: establishing a connection between the communication device and a serving base station; determining whether to relax a condition for declaring an RLF; using a first rule in declaring an RLF in response to determining that the communication device should not relax the condition; and using a relaxed rule in declaring an RLF in response to determining that the communication device should relax the condition, wherein the relaxed rule is less stringent than the first rule.