[ns] Catch packets in any node

[Alexandre Malhão]

Hi,

I'm trying to find a way do catch and modify packets that pass through a 
node.

I have a structure like this:

(tcp)N0--------N1--------N2(sink)

There are no agents associated to N1.

I need to catch a packet in node N1, modify it and send it to right 
destenation (in this case N2).

Does anyone know how to do it??

 I'm quite desperate, so I would be very greatful if anyone could help 
me please.

Best regards,

Alexandre Malhão