We have a Cisco 1751 on our T1/E1 line and we want to throw in a Watchguard SOHO 6tc VPN through it. Both devices work fine, until we plug them into each other. The Cisco seems to die and nothing will work. We are using DES/3DES encryption on the WG. Is this a simple memory issue, or is there a compatibility problem with the Cisco OS? Any help would be greatly appreciated!