Q: loading WinPcap dynamic libraries from cygwin/libnet 1.1.2.1

Here's a question about loading WinPcap dynamic libraries from 
cygwin/libnet 1.1.2.1

First setup:
 - Windows XP Service Pack 1
 - cygwin 1.5.10-3
 - WinPcap 3.1 beta 3
 - libnet 1.1.2.1
 - libnet-cygwin-diffs

I installed cygwin and WinPcap.  Then, I unpacked libnet and 
applied the diffs.  The build of libnet worked, and the libnet 
applications work.

I had to change the OS on this machine to Windows 2000 SP4.
However, libnet applications can not load the dynamic library
'packet'.  After some experimentation, libnet applications can
load the dynamic library packet if I rename 'packet.dll' to
'packet'.

Can someone add some details about this change in behavior?

TIA,
Daryl