[Openswan Users] fire pluto[2196]: "test" #11880: Informational Exchange message is invalid because it has a previously used Message ID (0x55dccabb)

[openswan]

Hello,

What does this message mean?

 fire pluto[2196]: "test" #11880: Informational Exchange message is
invalid because it has a previously used Message ID (0x55dccabb)


It appears only if I set dpddelay parameter to whatever value. Does it
mean that the remote end (NETGEAR router) does not support DPD (Death
Peer Detection) or DPD is not switched on?


Thanks