diff -urp src.old/winsup/cygwin/fork.cc src/winsup/cygwin/fork.cc
--- src.old/winsup/cygwin/fork.cc	Wed Jun 19 02:17:03 2002
+++ src/winsup/cygwin/fork.cc	Fri Aug 16 12:43:55 2002
@@ -311,8 +311,6 @@ fork_child (HANDLE& hParent, dll *&first
     if ((*t)->clear_on_fork ())
       (*t)->set ();
 
-  user_data->threadinterface->fixup_after_fork ();
-
   /* Initialize signal/process handling */
   sigproc_init ();
   __pthread_atforkchild ();
diff -urp src.old/winsup/cygwin/thread.cc src/winsup/cygwin/thread.cc
--- src.old/winsup/cygwin/thread.cc	Fri Aug 16 11:46:06 2002
+++ src/winsup/cygwin/thread.cc	Fri Aug 16 12:49:42 2002
@@ -301,6 +301,7 @@ MTinterface::Init (int forked)
   if (forked)
     return;
 
+  keys = NULL;
   mutexs = NULL;
   conds  = NULL;
   semaphores = NULL;
@@ -316,10 +317,29 @@ MTinterface::Init (int forked)
 #endif
 }
 
+void
+MTinterface::fixup_before_fork (void)
+{
+  pthread_key *key = keys;
+  debug_printf ("keys is %x",keys);
+  while (key)
+    {
+      key->fixup_before_fork ();
+      key = key->next;
+    }
+}
+
 /* This function is called from a single threaded process */
 void
 MTinterface::fixup_after_fork (void)
 {
+  pthread_key *key = keys;
+  debug_printf ("keys is %x",keys);
+  while (key)
+    {
+      key->fixup_after_fork ();
+      key = key->next;
+    }
   pthread_mutex *mutex = mutexs;
   debug_printf ("mutexs is %x",mutexs);
   while (mutex)
@@ -974,6 +994,8 @@ pthread_key::pthread_key (void (*destruc
       MT_INTERFACE->destructors.
 	Insert (new pthread_key_destructor (destructor, this));
     }
+  /* threadsafe addition is easy */
+  next = (pthread_key *) InterlockedExchangePointer (&MT_INTERFACE->keys, this);
 }
 
 pthread_key::~pthread_key ()
@@ -981,6 +1003,18 @@ pthread_key::~pthread_key ()
   if (pthread_key_destructor *dest = MT_INTERFACE->destructors.Remove (this))
     delete dest;
   TlsFree (dwTlsIndex);
+
+  /* I'm not 100% sure the next bit is threadsafe. I think it is... */
+  if (MT_INTERFACE->keys == this)
+    InterlockedExchangePointer (&MT_INTERFACE->keys, this->next);
+  else
+    {
+      pthread_key *tempkey = MT_INTERFACE->keys;
+      while (tempkey->next && tempkey->next != this)
+        tempkey = tempkey->next;
+      /* but there may be a race between the loop above and this statement */
+      InterlockedExchangePointer (&tempkey->next, this->next);
+    }
 }
 
 int
@@ -998,6 +1032,21 @@ pthread_key::get ()
   return TlsGetValue (dwTlsIndex);
 }
 
+void
+pthread_key::fixup_before_fork ()
+{
+  fork_buf = get ();
+}
+
+void
+pthread_key::fixup_after_fork ()
+{
+  dwTlsIndex = TlsAlloc ();
+  if (dwTlsIndex == TLS_OUT_OF_INDEXES)
+    api_fatal ("pthread_key::fixup_after_fork () failed to reallocate Tls storage");
+  set (fork_buf);
+}
+
 /*pshared mutexs:
 
  * REMOVED FROM CURRENT. These can be reinstated with the daemon, when all the
@@ -1382,6 +1431,8 @@ __pthread_cancel (pthread_t thread)
 void
 __pthread_atforkprepare (void)
 {
+  MT_INTERFACE->fixup_before_fork ();
+
   callback *cb = MT_INTERFACE->pthread_prepare;
   while (cb)
     {
@@ -1404,6 +1455,8 @@ __pthread_atforkparent (void)
 void
 __pthread_atforkchild (void)
 {
+  MT_INTERFACE->fixup_after_fork ();
+
   callback *cb = MT_INTERFACE->pthread_child;
   while (cb)
     {
diff -urp src.old/winsup/cygwin/thread.h src/winsup/cygwin/thread.h
--- src.old/winsup/cygwin/thread.h	Fri Aug 16 11:46:06 2002
+++ src/winsup/cygwin/thread.h	Fri Aug 16 12:38:11 2002
@@ -178,9 +178,15 @@ class pthread_key:public verifyable_obje
 public:
 
   DWORD dwTlsIndex;
+  void *fork_buf;
+  class pthread_key *next;
+
   int set (const void *);
   void *get ();
 
+  void fixup_before_fork ();
+  void fixup_after_fork ();
+
     pthread_key (void (*)(void *));
    ~pthread_key ();
 };
@@ -399,12 +405,14 @@ public:
   callback *pthread_child;
   callback *pthread_parent;
 
-  // list of mutex's. USE THREADSAFE INSERTS AND DELETES.
+  // lists of pthread objects. USE THREADSAFE INSERTS AND DELETES.
+  class pthread_key   * keys;
   class pthread_mutex * mutexs;
   class pthread_cond  * conds;
   class semaphore     * semaphores;
 
   void Init (int);
+  void fixup_before_fork (void);
   void fixup_after_fork (void);
 
   MTinterface ():reent_index (0), indexallocated (0), threadcount (1)