Externally transparent routing

Hello all,

To prevent my NAT-box from showing up on traceroutes I'd like to let it route without decreasing the TTL. I was told that proxy arp also archieves this, however I have no need for proxy arp per se and am also not completely confident that that will do what I want. I also saw TTL decrease/increase settings in the iptables mangling options, however I use 2.2 and would rather not upgrade. So my question is: is this possible under 2.2 and if so, how?

Thanks in advance,
Jordi Verwer

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