diff --git a/tasks/libl4/include/l4lib/utcb.h b/tasks/libl4/include/l4lib/utcb.h
index f6b5c6d..ece82ab 100644
--- a/tasks/libl4/include/l4lib/utcb.h
+++ b/tasks/libl4/include/l4lib/utcb.h
@@ -7,4 +7,6 @@
 #include <l4lib/types.h>
 #include <l4lib/arch/utcb.h>
 
+int utcb_init(void);
+
 #endif /* __UTCB_H__ */
diff --git a/tasks/libl4/src/init.c b/tasks/libl4/src/init.c
index fac5c10..9aca7d0 100644
--- a/tasks/libl4/src/init.c
+++ b/tasks/libl4/src/init.c
@@ -75,7 +75,8 @@ static void *l4_utcb_page(void)
 
 /*
  * Initialises a non-pager task's shared memory utcb page
- * using posix semantics.
+ * using posix semantics. Used during task initialisation
+ * and by child tasks after a fork.
  */
 int utcb_init(void)
 {
diff --git a/tasks/libposix/fork.c b/tasks/libposix/fork.c
index 8fbc255..b532544 100644
--- a/tasks/libposix/fork.c
+++ b/tasks/libposix/fork.c
@@ -39,8 +39,11 @@ int fork(void)
 		errno = -ret;
 		return -1;
 	}
-	/* else return value */
-	return ret;
 
+	/* If we're a child, we need to initialise the utcb page */
+	if (ret == 0)
+		utcb_init();
+
+	return ret;
 }