[c-nsp] setting source address for icmp messages

[Mike]

Hello,

I'm trying to learn how to get my 7204vxr to not send icmp messages with 
the source ip of interface the message is being sent out. I have a 
public ip on my loopback and thought this was what ios preferred if it 
exists? I have some other interfaces which have 10.x.x.x addresses and 
icmp messages like host unreachable and such are sourced from this which 
is undesirable due to inbound filtering at many sites at their gateways 
for rfc1918 and other bogon addresses.

Am I being silly to want this or is there something I can do to get my 
way here?

Tks.

Mike-