diff --git a/drivers/isdn/mISDN/tei.c b/drivers/isdn/mISDN/tei.c
index 6d4da60..34e898f 100644
--- a/drivers/isdn/mISDN/tei.c
+++ b/drivers/isdn/mISDN/tei.c
@@ -16,6 +16,7 @@
  */
 #include "layer2.h"
 #include <linux/random.h>
+#include <linux/slab.h>
 #include "core.h"
 
 #define ID_REQUEST	1