[Click] Click stops answering ping requests

[Thomas Weber]

Hello!

I think of using click as IPv4/IPv6 NA(P)T-PT Proxy/Router. But 
currently I still encounter problems with a very simple configuration:

-- 8< -- simple_config.click --
AddressInfo( extern_if 192.168.101.15 00:10:f3:03:2a:5d );

elementclass GatewayDevice {
     $device |
     from :: FromDevice($device) -> output;
     input
         -> q :: Queue(1024)
         -> to :: ToDevice($device);
     ScheduleInfo(from .1, to 1);
}

io_dev :: GatewayDevice(eth0);

// arp classifier:
//     [0] ARP requests
//     [1] ARP replies
//     [2] IPv4
//     [3] other
io_arp_classifier :: Classifier(
     12/0806 20/0001,
     12/0806 20/0002,
     12/0800,
     -
);

// IPv4 ARP
IPv4_arpr :: ARPResponder(extern_if)
     -> io_dev;
IPv4_arpq :: ARPQuerier(extern_if)
     -> io_dev;
Idle -> [0]IPv4_arpq; // dummy

IPv4_handler :: Strip(14)   // strip ethernet header
     -> CheckIPHeader(extern_if)
     -> EtherEncap(0x0800, 1:1:1:1:1:1, extern_if)  // fake eth-header
     -> Print(ToHost)
     -> ToHost;

// ingoing traffic
io_dev -> io_arp_classifier;
io_arp_classifier[0] -> IPv4_arpr;
io_arp_classifier[1] -> [1]IPv4_arpq;
io_arp_classifier[2] -> IPv4_handler;
io_arp_classifier[3] -> Print(dropped) -> Discard;
-- 8< -- simple_config.click --

I compiled click as a module for linux kernel 2.6.13 (CVS patch 
applied). When running 'click-install simple_config.click', a new router 
thread is started. Everything is working fine, but after about 20 
seconds or so, the host stops answering to ping requests (as well as any 
other). On my local console, I still can see ICMP packets to be 
forwarded to host and arpinging the host still works.
What's wrong about my configuration?

Thanks a lot in advance and greetings from munich,
Thomas