We are having a problem periodically having to clear the xlate on our FWSM. We have a failover pair in 6509's. For some reason they stop passing all traffic. We clear xlate and everything runs fine for a random amount of time. Sometimes for a couple weeks sometimes for a couple months. We have installed the latest software, replaced, the hardware, compared the config between the primary and standby. Appears to be totally random. We have other FWSM in the network without experiencing this problm.