diff --git a/headers/private/kernel/arch/thread.h b/headers/private/kernel/arch/thread.h
index 787aea24ab..225f001c9b 100644
--- a/headers/private/kernel/arch/thread.h
+++ b/headers/private/kernel/arch/thread.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2004, Axel Dörfler, axeld@pinc-software.de.
+ * Copyright 2002-2007, Axel Dörfler, axeld@pinc-software.de.
  * Distributed under the terms of the MIT License.
  *
  * Copyright 2001-2002, Travis Geiselbrecht. All rights reserved.
@@ -19,7 +19,7 @@ extern "C" {
 status_t arch_thread_init(struct kernel_args *args);
 status_t arch_team_init_team_struct(struct team *t, bool kernel);
 status_t arch_thread_init_thread_struct(struct thread *t);
-void arch_thread_init_tls(struct thread *thread);
+status_t arch_thread_init_tls(struct thread *thread);
 void arch_thread_context_switch(struct thread *t_from, struct thread *t_to);
 status_t arch_thread_init_kthread_stack(struct thread *t, int (*start_func)(void), void (*entry_func)(void), void (*exit_func)(void));
 void arch_thread_dump_info(void *info);
diff --git a/src/system/kernel/arch/ppc/arch_thread.c b/src/system/kernel/arch/ppc/arch_thread.c
index 05f844eaac..903b1c37bf 100644
--- a/src/system/kernel/arch/ppc/arch_thread.c
+++ b/src/system/kernel/arch/ppc/arch_thread.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2003-2006, Haiku Inc. All rights reserved.
+ * Copyright 2003-2007, Haiku Inc. All rights reserved.
  * Distributed under the terms of the MIT License.
  *
  * Authors:
@@ -160,10 +160,11 @@ arch_thread_init_kthread_stack(struct thread *t, int (*start_func)(void),
 }
 
 
-void
+status_t
 arch_thread_init_tls(struct thread *thread)
 {
-// TODO: Implement!
+	// TODO: Implement!
+	return B_OK;
 }
 
 
diff --git a/src/system/kernel/arch/x86/arch_thread.c b/src/system/kernel/arch/x86/arch_thread.c
index d66f5b8b42..2f115c118f 100644
--- a/src/system/kernel/arch/x86/arch_thread.c
+++ b/src/system/kernel/arch/x86/arch_thread.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2005, Axel Dörfler, axeld@pinc-software.de.
+ * Copyright 2002-2007, Axel Dörfler, axeld@pinc-software.de.
  * Distributed under the terms of the MIT License.
  *
  * Copyright 2001, Travis Geiselbrecht. All rights reserved.
@@ -229,17 +229,19 @@ arch_thread_init_kthread_stack(struct thread *t, int (*start_func)(void), void (
  *	Is called from _create_user_thread_kentry().
  */
 
-void
+status_t
 arch_thread_init_tls(struct thread *thread)
 {
-	uint32 *tls;
+	uint32 tls[TLS_THREAD_ID_SLOT + 1];
+	int32 i;
 
 	thread->user_local_storage = thread->user_stack_base + thread->user_stack_size;
-	tls = (uint32 *)thread->user_local_storage;
 
+	// initialize default TLS fields
 	tls[TLS_BASE_ADDRESS_SLOT] = thread->user_local_storage;
 	tls[TLS_THREAD_ID_SLOT] = thread->id;
-	tls[TLS_ERRNO_SLOT] = 0;
+
+	return user_memcpy((void *)thread->user_local_storage, tls, sizeof(tls));
 }