Then it wouldn't/shouldn't be looking for X11/* (aka the stuff I pointed out earlier).

update: maybe you should read a little closer? (rhetorical).

README.cygwin says

CONFIGURE/BUILD

    Use native Win32 GUI calls:

        perl Makefile.PL

    Use X11 client libraries (and requires a X server):

        Precompiled X11 client libraries can be downloaded from
        ftp://sourceware.cygnus.com/pub/cygwin/xfree/xc-4-binaries/
            xfree86-4.0-DLLs.tar.bz2
            xfree86-4.0-devel.tar.bz2

        NOTE: Your DISPLAY must be 127.0.0.1:0.0
              Your PATH must include the DLL directory, /usr/X11R6/bin

        perl Makefile.PL x

    make

I don't see any mention of ./configure in README.cygwin, which leads me to conclude that you should read README.cygwin again, so please do so.

MJD says you can't just make shit up and expect the computer to know what you mean, retardo! ** The Third rule of perl club is a statement of fact: pod is sexy.