Netflow iptables module

Compiling for kernel 2.6.18-164.el5
make -C /lib/modules/2.6.18-164.el5/build M=/root/distr/netflow/ipt_netflow
modules
make[1]: Entering directory `/usr/src/kernels/2.6.18-164.el5-x86_64'
CC [M] /root/distr/netflow/ipt_netflow/ipt_NETFLOW.o
Building modules, stage 2.
MODPOST
CC /root/distr/netflow/ipt_netflow/ipt_NETFLOW.mod.o
LD [M] /root/distr/netflow/ipt_netflow/ipt_NETFLOW.ko
make[1]: Leaving directory `/usr/src/kernels/2.6.18-164.el5-x86_64'
gcc -O2 -Wall -Wunused -I/lib/modules/2.6.18-164.el5/build/include
-I/root/distr/iptables/iptables-1.3.5/include -DIPTABLES_V
ERSION=\"1.3.5\" -fPIC -o libipt_NETFLOW_sh.o -c libipt_NETFLOW.c
gcc -shared -o libipt_NETFLOW.so libipt_NETFLOW_sh.o
libipt_NETFLOW_sh.o: In function `_init':
libipt_NETFLOW.c:(.text+0x30): multiple definition of `_init'
/usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../lib64/crti.o:(.init+0x0)
: first defined here
collect2: ld returned 1 exit status
make: *** [libipt_NETFLOW.so] Error 1

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