diff --git a/configure.ac b/configure.ac
index b6ed92cb3..86153ec81 100644
--- a/configure.ac
+++ b/configure.ac
@@ -420,7 +420,7 @@ case $host_os in
   darwin*)
 	AC_DEFINE(CSRG_BASED, 1, [System is BSD-like])
 	;;
-  cygwin*)
+  cygwin*|mingw*)
 	CFLAGS="$CFLAGS -DFD_SETSIZE=256"
 	;;
 esac
@@ -1904,7 +1904,7 @@ if test "x$XWIN" = xyes; then
 			XWIN_SERVER_NAME=Xming
 			AC_DEFINE(RELOCATE_PROJECTROOT,1,[Make PROJECT_ROOT relative to the xserver location])
 			AC_DEFINE(HAS_WINSOCK,1,[Use Windows sockets])
-			XWIN_SYS_LIBS=-lws2_32
+			XWIN_SYS_LIBS="-lpthread -lws2_32"
 			;;
 	esac
 
diff --git a/doc/c-extensions b/doc/c-extensions
index eb33e272b..4a9006150 100644
--- a/doc/c-extensions
+++ b/doc/c-extensions
@@ -35,7 +35,7 @@ The server will not build if your toolchain does not support these extensions.
     * interleaved code and declarations: { foo = TRUE; int bar; do_stuff(); }
 
 
-Use of OS and library facilities throughout the X server tree
+Use of library facilities throughout the X server tree
 -------------------------------------------------------------
 
 Non-OS-dependent code can assume facilities at least as good as
@@ -44,6 +44,17 @@ be C99, but even gcc+glibc doesn't implement that yet.
 
 Unix-like systems are assumed to be at least as good as UNIX03.
 
+Note that there are two Windows ports, Cygwin and MinGW:
+- Cygwin is more or less like Linux.
+- MinGW is more restrictive. Windows does not provide the required
+POSIX facilities, so some non-OS-dependent code is stubbed out or
+has an alternate implementation if WIN32 is defined.  Code that
+needs to be portable to Windows should be careful to, well, be portable.
+
+
+Required OS facilities
+-------------------------------------------------------------
+
 Linux systems must be at least 2.4 or later.  As a practical matter
 though, 2.4 kernels never receive any testing.  Use 2.6 already.
 
@@ -51,11 +62,7 @@ TODO: Solaris.
 
 TODO: *BSD.
 
-Code that needs to be portable to Windows should be careful to,
-well, be portable.  Note that there are two Windows ports, cygwin and
-mingw.  Cygwin is more or less like Linux, but mingw is a bit more
-restrictive.  TODO: document which versions of Windows we actually care
-about.
+Windows-dependent code assumes at least NT 5.1.
 
 OSX support is generally limited to the most recent version.  Currently
 that means 10.5.
diff --git a/hw/xwin/winprefs.c b/hw/xwin/winprefs.c
index dbc5b5228..6cbd7ad80 100644
--- a/hw/xwin/winprefs.c
+++ b/hw/xwin/winprefs.c
@@ -645,6 +645,7 @@ winPrefsLoadPreferences(char *path)
 
     if (path)
         prefFile = fopen(path, "r");
+#ifdef __CYGWIN__
     else {
         char defaultPrefs[] =
             "MENU rmenu {\n"
@@ -656,6 +657,7 @@ winPrefsLoadPreferences(char *path)
         path = "built-in default";
         prefFile = fmemopen(defaultPrefs, strlen(defaultPrefs), "r");
     }
+#endif
 
     if (!prefFile) {
         ErrorF("LoadPreferences: %s not found\n", path);
diff --git a/os/utils.c b/os/utils.c
index 04bcbc61f..3c520add5 100644
--- a/os/utils.c
+++ b/os/utils.c
@@ -235,6 +235,19 @@ OsSignal(int sig, OsSigHandlerPtr handler)
 #define LOCK_PREFIX "/.X"
 #define LOCK_SUFFIX "-lock"
 
+#if !defined(WIN32) || defined(__CYGWIN__)
+#define LOCK_SERVER
+#endif
+
+#ifndef LOCK_SERVER
+void
+LockServer(void)
+{}
+
+void
+UnlockServer(void)
+{}
+#else /* LOCK_SERVER */
 static Bool StillLocking = FALSE;
 static char LockFile[PATH_MAX];
 static Bool nolock = FALSE;
@@ -382,6 +395,7 @@ UnlockServer(void)
         (void) unlink(LockFile);
     }
 }
+#endif /* LOCK_SERVER */
 
 /* Force connections to close on SIGHUP from init */
 
@@ -503,7 +517,9 @@ UseMsg(void)
 #ifdef RLIMIT_STACK
     ErrorF("-ls int                limit stack space to N Kb\n");
 #endif
+#ifdef LOCK_SERVER
     ErrorF("-nolock                disable the locking mechanism\n");
+#endif
     ErrorF("-nolisten string       don't listen on protocol\n");
     ErrorF("-noreset               don't reset after last client exists\n");
     ErrorF("-background [none]     create root window with no background\n");
@@ -664,7 +680,9 @@ ProcessCommandLine(int argc, char *argv[])
             if (++i < argc) {
                 displayfd = atoi(argv[i]);
                 display = NULL;
+#ifdef LOCK_SERVER
                 nolock = TRUE;
+#endif
             }
             else
                 UseMsg();
@@ -744,6 +762,7 @@ ProcessCommandLine(int argc, char *argv[])
                 UseMsg();
         }
 #endif
+#ifdef LOCK_SERVER
         else if (strcmp(argv[i], "-nolock") == 0) {
 #if !defined(WIN32) && !defined(__CYGWIN__)
             if (getuid() != 0)
@@ -753,6 +772,7 @@ ProcessCommandLine(int argc, char *argv[])
 #endif
                 nolock = TRUE;
         }
+#endif
         else if (strcmp(argv[i], "-nolisten") == 0) {
             if (++i < argc) {
                 if (_XSERVTransNoListen(argv[i]))