[j-nsp] Juniper and Cisco - GRE tunnel

[simon teh]

Hi all,

I have a question over here and have tried to find out the answer from the
forum thread, but failed to get the answer.
Did anyone experience this type of problem before:

Juniper(M20) ----------------GRE tunnel-----------------------Cisco(7206)

*Juniper Configuration*
> show configuration interfaces gr-0/1/0
unit 0 {
    tunnel {
        source 219.93.2.1;
        destination 219.93.2.2;
        key 123456;
    }
    family inet {
        mtu 1514;
        address 192.168.1.1/30;
    }
}

*Cisco Configuration*
interface
Tunnel0
 ip address 192.168.1.2 255.255.255.252

 no ip
unreachables
 no ip
proxy-arp
 ip mtu
1514
 tunnel source 219.93.2.2
 tunnel destination 219.93.2.1
 tunnel key 123456

The problem I had was if I configured both router WITHOUT the tunnel key,
everything looks FINE. However once I include the tunnel key, then both
tunnel UNABLE to ping (interface still up, up). Does anyone has any idea
about the tunnel key between Juniper and Cisco. I am confident that other
configuration is good, it is the problem with the key.
Any suggestion?

Thank you very much.