Problem compiling libnet 1.1.2 with latest cygwin

Hello,

I'm quite a newbie so perhaps i made a mistake but i didn't managed to 
compile libnet 1.1.2 with cygwin (installed a week ago) on xp pro sp1.

So here is what i've done :

1. install cygwin (made a week ago)

2. install winpcap 3.1 beta from 
http://winpcap.polito.it/install/default.htm

3. download developer's pack 3.1 beta and unzip in d:\downloads\WpdPack

4. copy the content of the include folder of WpdPack to 
/usr/include/pcap (actually c:\programs\cygwin\usr\include\pcap) as it 
is stated in the file PORTED of libnet 1.1.2 (int the doc folder)

5. copy libpacket.a and libwpcap.a to /lib (c:\programs\cygwin\lib)

6. i also copy Packet.dll, pthreadVC.dll and WanPacket.dll to /bin 
(although i think it's not recquired)

5. unzip libnet archive to d:\download\libnet

6. and from a cygwin prompt : ./configure

So here i'ev got the "classical" error :

error: packet lib not found.

NB : if i modify the configure file to pass it, i've got the next error :

error: pcap lib not found

I saw people having the same problem with previous version but... And it 
seems i did exacty what stated in the doc...

Need help ;) At least to know if it's possible or not ? and if it is, 
how ???

Thanks a lot,

Math'