Cisco 2811

Hi,

I have a Cisco 2811 router, i already have enabled the syslog to my ManageEngineFirewall server. I already have 4 Cisco PIx that are being logged in that same ManageEngine server and I can see all the graphs, statistis, logs, but nothing shows up for the 2811, and it doesn't even recognize it as an unknown device.

Any Ideas?
Thanks,