diff --git a/gst/cothreads.c b/gst/cothreads.c
index e9cd26184b..4c8747515b 100644
--- a/gst/cothreads.c
+++ b/gst/cothreads.c
@@ -76,6 +76,13 @@ cothread_init (void)
   ctx->threads[0]->sp = (int *)CURRENT_STACK_FRAME;
   ctx->threads[0]->pc = 0;
 
+  // initialize the lock
+#ifdef COTHREAD_ATOMIC
+  atomic_set (&ctx->threads[0]->lock, 0);
+#else
+  ctx->threads[0]->lock = g_mutex_new();
+#endif
+
   GST_INFO (GST_CAT_COTHREADS,"0th thread is %p at sp:%p",ctx->threads[0], ctx->threads[0]->sp);
 
   // we consider the initiating process to be cothread 0
@@ -176,6 +183,11 @@ cothread_stub (void)
   GST_DEBUG_ENTER("");
 
   thread->flags |= COTHREAD_STARTED;
+#ifdef COTHREAD_ATOMIC
+  // do something here to lock
+#else
+  g_mutex_lock(thread->lock);
+#endif
   while (1) {
     thread->func(thread->argc,thread->argv);
     // we do this to avoid ever returning, we just switch to 0th thread
@@ -262,6 +274,20 @@ cothread_switch (cothread_state *thread)
 #endif
   if (current == thread) goto selfswitch;
 
+  // unlock the current thread, we're out of that context now
+#ifdef COTHREAD_ATOMIC
+  // do something to unlock the cothread
+#else
+  g_mutex_unlock(current->lock);
+#endif
+
+  // lock the next cothread before we even switch to it
+#ifdef COTHREAD_ATOMIC
+  // do something to lock the cothread
+#else
+  g_mutex_lock(thread->lock);
+#endif
+
   // find the number of the thread to switch to
   GST_INFO (GST_CAT_COTHREAD_SWITCH,"switching from cothread #%d to cothread #%d",
             ctx->current,thread->threadnum);
@@ -313,3 +339,35 @@ selfswitch:
   g_print("cothread: trying to switch to same thread, legal but not necessary\n");
   return;
 }
+
+
+void
+cothread_lock (cothread_state *thread)
+{
+#ifdef COTHREAD_ATOMIC
+  // do something to lock the cothread
+#else
+  g_mutex_lock(thread->lock);
+#endif
+}
+
+gboolean
+cothread_trylock (cothread_state *thread)
+{
+#ifdef COTHREAD_ATOMIC
+  // do something to try to lock the cothread
+#else
+  return g_mutex_trylock(thread->lock);
+#endif
+}
+
+void
+cothread_unlock (cothread_state *thread)
+{
+#ifdef COTHREAD_ATOMIC
+  // do something to unlock the cothread
+#else
+  g_mutex_unlock(thread->lock);
+#endif
+}
+
diff --git a/gst/cothreads.h b/gst/cothreads.h
index 270c4d4c81..40092f5b07 100644
--- a/gst/cothreads.h
+++ b/gst/cothreads.h
@@ -26,8 +26,14 @@
 #include <glib.h>
 #include <setjmp.h>
 
-#define COTHREAD_STACKSIZE 8192
-#define COTHREAD_MAXTHREADS 16
+#ifdef HAVE_ATOMIC_H
+#include <asm/atomic.h>
+#endif
+
+#undef COTHREAD_ATOMIC
+
+#define COTHREAD_STACKSIZE 32768
+#define COTHREAD_MAXTHREADS 64
 #define STACK_SIZE 0x200000
 
 #ifndef CURRENT_STACK_FRAME
@@ -51,10 +57,16 @@ struct _cothread_state {
 
   int flags;
   void *sp;
+  jmp_buf jmp;
   /* is this needed any more? */
   void *top_sp;
   void *pc;
-  jmp_buf jmp;
+
+#ifdef COTHREAD_ATOMIC
+  atomic_t lock;
+#else
+  GMutex *lock;
+#endif
 };
 
 struct _cothread_context {
@@ -73,6 +85,10 @@ void				cothread_switch		(cothread_state *thread);
 void				cothread_set_data	(cothread_state *thread, gchar *key, gpointer data);
 gpointer			cothread_get_data	(cothread_state *thread, gchar *key);
 
+void				cothread_lock		(cothread_state *thread);
+gboolean			cothread_trylock	(cothread_state *thread);
+void				cothread_unlock		(cothread_state *thread);
+
 cothread_state*			cothread_main		(cothread_context *ctx);
 
 #endif /* __COTHREAD_H__ */
diff --git a/gst/gstelement.c b/gst/gstelement.c
index ccb843e591..361af129f3 100644
--- a/gst/gstelement.c
+++ b/gst/gstelement.c
@@ -49,6 +49,9 @@ enum {
 static void			gst_element_class_init		(GstElementClass *klass);
 static void			gst_element_init		(GstElement *element);
 
+static void			gst_element_set_arg	(GtkObject *object, GtkArg *arg, guint id);
+static void			gst_element_get_arg	(GtkObject *object, GtkArg *arg, guint id);
+
 static void			gst_element_real_destroy	(GtkObject *object);
 
 static GstElementStateReturn	gst_element_change_state	(GstElement *element);
@@ -68,8 +71,8 @@ GtkType gst_element_get_type(void) {
       sizeof(GstElementClass),
       (GtkClassInitFunc)gst_element_class_init,
       (GtkObjectInitFunc)gst_element_init,
-      (GtkArgSetFunc)NULL,
-      (GtkArgGetFunc)NULL,
+      (GtkArgSetFunc)gst_element_set_arg,
+      (GtkArgGetFunc)gst_element_get_arg,
       (GtkClassInitFunc)NULL,
     };
     element_type = gtk_type_unique(GST_TYPE_OBJECT,&element_info);
@@ -116,6 +119,8 @@ gst_element_class_init (GstElementClass *klass)
 
   gtk_object_class_add_signals (gtkobject_class, gst_element_signals, LAST_SIGNAL);
 
+  gtkobject_class->set_arg =		gst_element_set_arg;
+  gtkobject_class->get_arg =		gst_element_get_arg;
   gtkobject_class->destroy =		gst_element_real_destroy;
 
   gstobject_class->save_thyself =	gst_element_save_thyself;
@@ -138,6 +143,35 @@ gst_element_init (GstElement *element)
   element->sched = NULL;
 }
 
+
+static void
+gst_element_set_arg (GtkObject *object, GtkArg *arg, guint id)
+{
+  GstElementClass *oclass = GST_ELEMENT_CLASS (object->klass);
+
+  GST_SCHEDULE_LOCK_ELEMENT ( GST_ELEMENT_SCHED(object), GST_ELEMENT(object) );
+
+  if (oclass->set_arg)
+    (oclass->set_arg)(object,arg,id);
+
+  GST_SCHEDULE_UNLOCK_ELEMENT ( GST_ELEMENT_SCHED(object), GST_ELEMENT(object) );
+}
+
+
+static void
+gst_element_get_arg (GtkObject *object, GtkArg *arg, guint id)
+{
+  GstElementClass *oclass = GST_ELEMENT_CLASS (object->klass);
+
+  GST_SCHEDULE_LOCK_ELEMENT (GST_ELEMENT_SCHED(object), GST_ELEMENT(object) );
+
+  if (oclass->get_arg)
+    (oclass->get_arg)(object,arg,id);
+
+  GST_SCHEDULE_UNLOCK_ELEMENT (GST_ELEMENT_SCHED(object), GST_ELEMENT(object) );
+}
+
+
 /**
  * gst_element_new:
  *
diff --git a/gst/gstelement.h b/gst/gstelement.h
index bc91ab2686..efa9982b7d 100644
--- a/gst/gstelement.h
+++ b/gst/gstelement.h
@@ -167,6 +167,14 @@ struct _GstElementClass {
   void (*error)		(GstElement *element,gchar *error);
   void (*eos)		(GstElement *element);
 
+  /* local pointers for get/set */
+  void (*set_arg) (GtkObject *object,
+                   GtkArg    *arg,
+                   guint      arg_id);
+  void (*get_arg) (GtkObject *object,
+                   GtkArg    *arg,
+                   guint      arg_id);      
+
   /* change the element state */
   GstElementStateReturn (*change_state)		(GstElement *element);
   /* request a new pad */
diff --git a/gst/gstscheduler.c b/gst/gstscheduler.c
index 2b8372e860..d7f709e392 100644
--- a/gst/gstscheduler.c
+++ b/gst/gstscheduler.c
@@ -773,6 +773,18 @@ void gst_bin_schedule_func(GstBin *bin) {
   }
 */
 
+static void 
+gst_schedule_lock_element (GstSchedule *sched,GstElement *element)
+{
+  cothread_lock(element->threadstate);
+}
+
+static void
+gst_schedule_unlock_element (GstSchedule *sched,GstElement *element)
+{
+  cothread_unlock(element->threadstate);
+}
+
 
 /*************** INCREMENTAL SCHEDULING CODE STARTS HERE ***************/
 
@@ -814,6 +826,8 @@ gst_schedule_init (GstSchedule *schedule)
   schedule->remove_element = GST_DEBUG_FUNCPTR(gst_schedule_remove_element);
   schedule->enable_element = GST_DEBUG_FUNCPTR(gst_schedule_enable_element);
   schedule->disable_element = GST_DEBUG_FUNCPTR(gst_schedule_disable_element);
+  schedule->lock_element = GST_DEBUG_FUNCPTR(gst_schedule_lock_element);
+  schedule->unlock_element = GST_DEBUG_FUNCPTR(gst_schedule_unlock_element);
   schedule->pad_connect = GST_DEBUG_FUNCPTR(gst_schedule_pad_connect);
   schedule->pad_disconnect = GST_DEBUG_FUNCPTR(gst_schedule_pad_disconnect);
   schedule->iterate = GST_DEBUG_FUNCPTR(gst_schedule_iterate);
diff --git a/gst/gstscheduler.h b/gst/gstscheduler.h
index b3a1e7b350..2a98f830b6 100644
--- a/gst/gstscheduler.h
+++ b/gst/gstscheduler.h
@@ -64,6 +64,8 @@ struct _GstSchedule {
   void (*remove_element)	(GstSchedule *sched, GstElement *element);
   void (*enable_element)	(GstSchedule *sched, GstElement *element);
   void (*disable_element)	(GstSchedule *sched, GstElement *element);
+  void (*lock_element)		(GstSchedule *sched, GstElement *element);
+  void (*unlock_element)	(GstSchedule *sched, GstElement *element);
   void (*pad_connect)		(GstSchedule *sched, GstPad *srcpad, GstPad *sinkpad);
   void (*pad_disconnect)	(GstSchedule *sched, GstPad *srcpad, GstPad *sinkpad);
   gboolean (*iterate)		(GstSchedule *sched);
@@ -83,6 +85,14 @@ struct _GstScheduleClass {
   GST_SCHEDULE_SAFETY ((sched)->enable_element((sched),(element)))
 #define GST_SCHEDULE_DISABLE_ELEMENT(sched,element) \
   GST_SCHEDULE_SAFETY ((sched)->disable_element((sched),(element)))
+
+#define GST_SCHEDULE_LOCK_ELEMENT(sched,element) \
+if ((sched)->lock_element != NULL) \
+((sched)->lock_element((sched),(element)))
+#define GST_SCHEDULE_UNLOCK_ELEMENT(sched,element) \
+if ((sched)->unlock_element != NULL) \
+((sched)->unlock_element((sched),(element)))
+
 #define GST_SCHEDULE_PAD_CONNECT(sched,srcpad,sinkpad) \
   GST_SCHEDULE_SAFETY ((sched)->pad_connect((sched),(srcpad),(sinkpad)))
 #define GST_SCHEDULE_PAD_DISCONNECT(sched,srcpad,sinkpad) \