martian source errors between networks

Hello
Some time ago mine logs start to show this message
-------------------
Apr 23 11:03:01 xxxxx kernel: [38048596.800691] martian source
192.168.0.87 from 217.15.41.137, on dev eth1
Apr 23 11:03:01 xxxxx kernel: [38048596.800691] martian source
192.168.0.87 from 217.15.41.137, on dev eth1
Apr 23 11:15:02 xxxxx kernel: [38049523.750307] martian source
192.168.0.87 from 217.15.41.137, on dev eth1
Apr 23 11:15:02 xxxxx kernel: [38049523.750307] martian source
192.168.0.87 from 217.15.41.137, on dev eth1
Apr 23 11:30:03 xxxxx kernel: [38050706.324262] martian source
192.168.0.87 from 217.15.41.137, on dev eth1
Apr 23 11:30:03 xxxxx kernel: [38050706.324262] martian source
192.168.0.87 from 217.15.41.137, on dev eth1
Apr 23 11:49:14 xxxxx kernel: [38052159.170082] martian source
192.168.0.87 from 217.15.41.137, on dev eth1
Apr 23 11:49:14 xxxxx kernel: [38052159.170082] martian source
192.168.0.87 from 217.15.41.137, on dev eth1
-------------------
I'm using debian5 with 2 network card, eth0(217.15.41.137) and eth1
(my local network) 192.168.0.xxx.
This server is used to host virtual machines and I think this is
something related to the openvz

I've been searching in google and I find some thing, but nothing that
I can use to understand what is causing this

I know that martian are usually ignored or at least that what I found,
but I think in a server with two networks and many virtuals machines,
that is not a good idea. It could mean that something is wrong and I
can't let it go that easily.

If someone know what could be causing this or can give any advice
about it, it would be lovely
Thank you very much