[j-nsp] GRE Keepalive on M10/M20

[Alireza Soltanian]

Hi Everybody
We have several M10/M20 with PE-Tunnel pics. I wonder how can I enable GRE
keepalive for GRE tunnels?
We also have M320 with PC-Tunnel pics. GRE keepalive works fine with GRE
tunnels on this PIC of M320 but for M10/M20 the related command was not
shown. Anyway When I configure it the command is accepted but GRE Keepalive
functionality does not work and I have an error about LFI interface
I searched the Internet but could not find anything. I must mention We use
JunOS 9 to 11 on these M10/M20

Thank you for your help and support...