diff --git a/m4/ax_check_glut.m4 b/m4/ax_check_glut.m4
index ed2f8a18fc..f883833084 100644
--- a/m4/ax_check_glut.m4
+++ b/m4/ax_check_glut.m4
@@ -38,7 +38,7 @@ else
     LIBS="${ax_try_lib} ${GLUT_LIBS} ${ax_save_LIBS}"
     AC_LINK_IFELSE(
     [AC_LANG_PROGRAM([[
-# if HAVE_WINDOWS_H && defined(_WIN32)
+# if HAVE_WINDOWS_H && (defined(_WIN32) || defined(CYGWIN_USE_WIN32))
 #   include <windows.h>
 # endif
 # include <GL/glut.h>]],
diff --git a/m4/ax_winsock.m4 b/m4/ax_winsock.m4
new file mode 100644
index 0000000000..fbe16215f8
--- /dev/null
+++ b/m4/ax_winsock.m4
@@ -0,0 +1,13 @@
+AC_DEFUN([AX_WINSOCK],[
+  AC_ARG_WITH([winsock],
+  	AC_HELP_STRING([--with-winsock],
+	 	[use windows sockets even if sys/socket.h exists]))
+  if test "${with_winsock}" = "yes" ; then
+    AC_DEFINE(USE_WINSOCK,[1],[Define to 1 to use windows sockets])
+    ac_cv_header_sys_socket_h="no"
+  else
+    ac_cv_header_winsock2_h="no"
+    ac_cv_header_winsock_h="no"
+  fi
+  AC_CHECK_HEADERS([windows.h winsock2.h winsock.h sys/socket.h])
+])
diff --git a/m4/boinc_check_cygwin.m4 b/m4/boinc_check_cygwin.m4
index ff344092d0..2fbc7161f2 100644
--- a/m4/boinc_check_cygwin.m4
+++ b/m4/boinc_check_cygwin.m4
@@ -9,6 +9,12 @@ AC_DEFUN([BOINC_CHECK_CYGWIN],[
   esac
   AC_MSG_RESULT($with_cygwin)
   if test "${with_cygwin}" = "yes" ; then
+    save_cflags="${CFLAGS}"
+    CFLAGS="-I/usr/include/w32api -D_WIN32 -DWIN32 ${CFLAGS}"
+  fi
+  AX_WINSOCK
+  if test "${with_cygwin}" = "yes" ; then
+    CFLAGS="${save_cflags}"
     AC_MSG_CHECKING([whether to use X11 or WIN32 GUI])
     if test "${with_x+set}" = set; then
        with_x="${with_x}"
diff --git a/m4/boinc_getsockopt.m4 b/m4/boinc_getsockopt.m4
index b51e9c8737..7f5fdfd971 100644
--- a/m4/boinc_getsockopt.m4
+++ b/m4/boinc_getsockopt.m4
@@ -1,6 +1,12 @@
 
 AC_DEFUN([BOINC_GETSOCKOPT_TYPE],[
 AC_LANG_PUSH(C)
+AC_CHECK_HEADERS([windows.h])
+if test "${ac_cv_header_windows_h}" = "yes" ; then
+  ac_includes_default="${ac_includes_default}
+#include <windows.h>
+"
+fi
 AC_CHECK_HEADERS([sys/socket.h])
 if test "${ac_cv_header_sys_socket_h}" = "yes" ; then
   ac_includes_default="${ac_includes_default}