diff --git a/contrib/sdk/sources/libsupc++/Makefile b/contrib/sdk/sources/libsupc++/Makefile
index dccf32f128..91069eeb4f 100644
--- a/contrib/sdk/sources/libsupc++/Makefile
+++ b/contrib/sdk/sources/libsupc++/Makefile
@@ -1,5 +1,5 @@
 
-LIBRARY= libsup++
+LIBRARY= libsupc++
 
 CC=gcc
 CPP=g++
diff --git a/contrib/sdk/sources/libsupc++/gthr-default.h b/contrib/sdk/sources/libsupc++/gthr-default.h
index bc09371e3c..53f8396cc8 100644
--- a/contrib/sdk/sources/libsupc++/gthr-default.h
+++ b/contrib/sdk/sources/libsupc++/gthr-default.h
@@ -72,8 +72,8 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #include <_mingw.h>
 #endif
 
-#ifndef ___GLIBCXX_UNUSED_PARAM
-#define ___GLIBCXX_UNUSED_PARAM(x) x
+#ifndef __UNUSED_PARAM
+#define __UNUSED_PARAM(x) x
 #endif
 
 #ifdef _LIBOBJC
@@ -295,7 +295,7 @@ __gthread_objc_mutex_unlock (objc_mutex_t mutex)
 
 /* Allocate a condition.  */
 int
-__gthread_objc_condition_allocate (objc_condition_t ___GLIBCXX_UNUSED_PARAM(condition))
+__gthread_objc_condition_allocate (objc_condition_t __UNUSED_PARAM(condition))
 {
   /* Unimplemented.  */
   return -1;
@@ -303,7 +303,7 @@ __gthread_objc_condition_allocate (objc_condition_t ___GLIBCXX_UNUSED_PARAM(cond
 
 /* Deallocate a condition.  */
 int
-__gthread_objc_condition_deallocate (objc_condition_t ___GLIBCXX_UNUSED_PARAM(condition))
+__gthread_objc_condition_deallocate (objc_condition_t __UNUSED_PARAM(condition))
 {
   /* Unimplemented.  */
   return -1;
@@ -311,8 +311,8 @@ __gthread_objc_condition_deallocate (objc_condition_t ___GLIBCXX_UNUSED_PARAM(co
 
 /* Wait on the condition */
 int
-__gthread_objc_condition_wait (objc_condition_t ___GLIBCXX_UNUSED_PARAM(condition),
-			       objc_mutex_t ___GLIBCXX_UNUSED_PARAM(mutex))
+__gthread_objc_condition_wait (objc_condition_t __UNUSED_PARAM(condition),
+			       objc_mutex_t __UNUSED_PARAM(mutex))
 {
   /* Unimplemented.  */
   return -1;
@@ -320,7 +320,7 @@ __gthread_objc_condition_wait (objc_condition_t ___GLIBCXX_UNUSED_PARAM(conditio
 
 /* Wake up all threads waiting on this condition.  */
 int
-__gthread_objc_condition_broadcast (objc_condition_t ___GLIBCXX_UNUSED_PARAM(condition))
+__gthread_objc_condition_broadcast (objc_condition_t __UNUSED_PARAM(condition))
 {
   /* Unimplemented.  */
   return -1;
@@ -328,7 +328,7 @@ __gthread_objc_condition_broadcast (objc_condition_t ___GLIBCXX_UNUSED_PARAM(con
 
 /* Wake up one thread waiting on this condition.  */
 int
-__gthread_objc_condition_signal (objc_condition_t ___GLIBCXX_UNUSED_PARAM(condition))
+__gthread_objc_condition_signal (objc_condition_t __UNUSED_PARAM(condition))
 {
   /* Unimplemented.  */
   return -1;
diff --git a/contrib/sdk/sources/libsupc++/gthr_mutex.c b/contrib/sdk/sources/libsupc++/gthr_mutex.c
index d750279ec3..f5cb8eb1a6 100644
--- a/contrib/sdk/sources/libsupc++/gthr_mutex.c
+++ b/contrib/sdk/sources/libsupc++/gthr_mutex.c
@@ -1,11 +1,65 @@
+#include <stdlib.h>
+#include <sys/errno.h>
+#include <kos32sys.h>
 
 void __mutex_lock(volatile int *val);
 
+static inline int tls_get(int key)
+{
+    int val;
+    __asm__ __volatile__(
+    "movl %%fs:(%1), %0"
+    :"=r"(val)
+    :"r"(key));
+
+  return val;
+};
+
+typedef struct {
+  int done;
+  long started;
+} __gthread_once_t;
+
 typedef struct {
   int counter;
   void *sema;
 } __gthread_mutex_t;
 
+typedef struct {
+  int counter;
+  int depth;
+  unsigned long owner;
+  int sema;
+} __gthread_recursive_mutex_t;
+
+
+int
+__gthr_win32_once (__gthread_once_t *once, void (*func) (void))
+{
+    if (once == NULL || func == NULL)
+        return EINVAL;
+
+    if (! once->done)
+    {
+        if (__sync_add_and_fetch (&(once->started), 1) == 0)
+        {
+            (*func) ();
+            once->done = 1;
+        }
+        else
+        {
+	  /* Another thread is currently executing the code, so wait for it
+	     to finish; yield the CPU in the meantime.  If performance
+	     does become an issue, the solution is to use an Event that
+	     we wait on here (and set above), but that implies a place to
+	     create the event before this routine is called.  */
+            while (! once->done)
+                delay(1);
+        }
+    }
+    return 0;
+}
+
 void __gthr_win32_mutex_init_function (__gthread_mutex_t *mutex)
 {
   mutex->counter = 0;
@@ -25,3 +79,72 @@ __gthr_win32_mutex_unlock (__gthread_mutex_t *mutex)
   return 0;
 }
 
+void
+__gthr_win32_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)
+{
+  mutex->counter = -1;
+  mutex->depth = 0;
+  mutex->owner = 0;
+  mutex->sema = 0;
+}
+
+void
+__gthr_win32_mutex_destroy (__gthread_mutex_t *mutex)
+{ }
+
+int
+__gthr_win32_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
+{
+    int me = tls_get(0);
+    if ( __sync_add_and_fetch(&mutex->counter, 1) == 0)
+    {
+        mutex->depth = 1;
+        mutex->owner = me;
+        mutex->sema  = 1;
+    }
+    else if (mutex->owner == me)
+    {
+        __sync_sub_and_fetch(&mutex->counter, 1);
+        ++(mutex->depth);
+    }
+    else
+    {
+        __mutex_lock(&mutex->sema);
+        mutex->depth = 1;
+        mutex->owner = me;
+    }
+    return 0;
+}
+
+int
+__gthr_win32_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
+{
+    int me = tls_get(0);
+    if (__sync_val_compare_and_swap (&mutex->counter, -1, 0) < 0)
+    {
+        mutex->depth = 1;
+        mutex->owner = me;
+        mutex->sema  = 1;
+    }
+    else if (mutex->owner == me)
+        ++(mutex->depth);
+    else
+        return 1;
+
+  return 0;
+}
+
+int
+__gthr_win32_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
+{
+    --(mutex->depth);
+    if (mutex->depth == 0)
+    {
+        mutex->owner = 0;
+
+        if (__sync_sub_and_fetch (&mutex->counter, 1) >= 0)
+            mutex->sema = 0;
+    }
+
+    return 0;
+}