diff --git a/stix/lib/exec.c b/stix/lib/exec.c
index 2be9714..f9a7fff 100644
--- a/stix/lib/exec.c
+++ b/stix/lib/exec.c
@@ -31,6 +31,10 @@
 #	include <windows.h>
 #elif defined(__MSDOS__)
 #	include <time.h>
+#elif defined(macintosh)
+#	include <Types.h>
+#	include <OSUtils.h>
+#	include <Timer.h>
 #else
 	/* TODO: remove this header after having changed clock_gettime() to a 
 	 *       platform independent function */
@@ -209,6 +213,14 @@ static STIX_INLINE void vm_gettime (stix_t* stix, stix_ntime_t* now)
 	#else
 	#	error UNSUPPORTED CLOCKS_PER_SEC
 	#endif
+#elif defined(macintosh)
+	UnsignedWide tick;
+	stix_uint64_t tick64;
+
+	Microseconds (&tick);
+
+	tick64 = *(stix_uint64_t*)&tick;
+	STIX_INITNTIME (now, STIX_USEC_TO_SEC(tick64), STIX_USEC_TO_NSEC(tick64));
 
 #elif defined(HAVE_CLOCK_GETTIME)
 	struct timespec ts;
@@ -242,6 +254,10 @@ static STIX_INLINE void vm_sleep (stix_t* stix, const stix_ntime_t* dur)
 		Sleep (STIX_SECNSEC_TO_MSEC(dur->sec,dur->nsec));
 	}
 
+#elif defined(macintosh)
+
+	/* TODO: ... */
+
 #elif defined(__MSDOS__) && defined(_INTELC32_)
 
 	clock_t c;
diff --git a/stix/lib/gc.c b/stix/lib/gc.c
index 2b4dbeb..898f700 100644
--- a/stix/lib/gc.c
+++ b/stix/lib/gc.c
@@ -341,12 +341,12 @@ printf ("STARTING GC curheap base %p ptr %p newheap base %p ptr %p\n",
 
 	for (i = 0; i < stix->sem_list_count; i++)
 	{
-		stix->sem_list[i] = (stix_oop_semaphore_t)stix_moveoop (stix, stix->sem_list[i]);
+		stix->sem_list[i] = (stix_oop_semaphore_t)stix_moveoop (stix, (stix_oop_t)stix->sem_list[i]);
 	}
 
 	for (i = 0; i < stix->sem_heap_count; i++)
 	{
-		stix->sem_heap[i] = (stix_oop_semaphore_t)stix_moveoop (stix, stix->sem_heap[i]);
+		stix->sem_heap[i] = (stix_oop_semaphore_t)stix_moveoop (stix, (stix_oop_t)stix->sem_heap[i]);
 	}
 
 	for (i = 0; i < stix->tmp_count; i++)
diff --git a/stix/lib/main.c b/stix/lib/main.c
index b23b765..100db71 100644
--- a/stix/lib/main.c
+++ b/stix/lib/main.c
@@ -47,7 +47,7 @@
 #elif defined(__MSDOS__)
 #	include <dos.h>
 #elif defined(macintosh)
-	/* nothing to include */
+#	include <Timer.h>
 #else
 #	include <unistd.h>
 #	include <ltdl.h>
@@ -404,6 +404,16 @@ static void timer_intr_handler (void)
 	_chain_intr(prev_timer_intr_handler);
 }
 
+#elif defined(macintosh)
+
+static TMTask g_tmtask;
+
+static pascal void timer_intr_handler (TMTask* task)
+{
+	if (g_stix) stix_switchprocess (g_stix);
+}
+
+
 #else
 static void arrange_process_switching (int sig)
 {
@@ -418,6 +428,18 @@ static void setup_tick (void)
 	prev_timer_intr_handler = _dos_getvect (0x1C);
 	_dos_setvect (0x1C, timer_intr_handler);
 
+#elif defined(macintosh)
+
+	long delay = 50;
+
+	memset (&g_tmtask, 0, STIX_SIZEOF(g_tmtask));
+	g_tmtask.tmAddr = NewTimerProc (timer_intr_handler);
+	InsXTime ((QElem*)&g_tmtask);
+
+	/* if delay is positive, it's in milliseconds.
+	 * if it's negative, it's in negated microsecond */
+	PrimeTime ((QElem*)&g_tmtask, delay);
+
 #elif defined(HAVE_SETITIMER) && defined(SIGVTALRM) && defined(ITIMER_VIRTUAL)
 	struct itimerval itv;
 	struct sigaction act;
@@ -444,6 +466,10 @@ static void cancel_tick (void)
 
 	_dos_setvect (0x1C, prev_timer_intr_handler);
 
+#elif defined(macintosh)
+	RmvTime ((QElem*)&g_tmtask);
+	/*DisposeTimerProc (g_tmtask.tmAddr);*/
+
 #elif defined(HAVE_SETITIMER) && defined(SIGVTALRM) && defined(ITIMER_VIRTUAL)
 	struct itimerval itv;
 	struct sigaction act;
@@ -454,7 +480,6 @@ static void cancel_tick (void)
 	itv.it_value.tv_usec = 0;
 	setitimer (ITIMER_VIRTUAL, &itv, STIX_NULL);
 
-
 	sigemptyset (&act.sa_mask);
 	act.sa_handler = SIG_DFL;
 	act.sa_flags = 0;