#1 Problems compiling on Mac OS X 10.6.6

Model Name: MacBook Pro
Model Identifier: MacBookPro7,1
Processor Name: Intel Core 2 Duo
Processor Speed: 2.4 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache: 3 MB
Memory: 4 GB
Bus Speed: 1.07 GHz
Boot ROM Version: MBP71.0039.B0B
SMC Version (system): 1.62f6

gnumake[1]: Nothing to be done for `all'.
Entering unilib
/bin/sh /Users/ronaldperris/Downloads/unicornscan-0.4.7/libtool --quiet --mode=compile gcc -g -O2 -O2 -DLIBDIR=\"/usr/local/lib\" -DSYSCONFDIR=\"/usr/local/etc\" -DLIBEXECDIR=\"/usr/local/libexec\" -DLOCALSTATEDIR=\"/usr/local/var\" -DPROGNAME=\"unicornscan\" -I/Users/ronaldperris/Downloads/unicornscan-0.4.7/src -I/Users/ronaldperris/Downloads/unicornscan-0.4.7/libs/fake/include -I/Users/ronaldperris/Downloads/unicornscan-0.4.7/ext_src -c intf.c
intf.c: In function 'get_interface_info':
intf.c:61: error: 'AF_PACKET' undeclared (first use in this function)
intf.c:61: error: (Each undeclared identifier is reported only once
intf.c:61: error: for each function it appears in.)
intf.c:62: error: dereferencing pointer to incomplete type
intf.c:66: error: dereferencing pointer to incomplete type
intf.c:66: error: dereferencing pointer to incomplete type
gnumake[2]: *** [intf.lo] Error 1
gnumake[1]: *** [alld] Error 1
make: *** [all] Error 1