diff --git a/libusb/driver.c b/libusb/driver.c
index b032712..33ee5d2 100644
--- a/libusb/driver.c
+++ b/libusb/driver.c
@@ -51,7 +51,7 @@ int usb_connect(const usb_device_id_t *filters, int nfilters, unsigned drvport)
 
 int usb_eventsWait(int port, msg_t *msg)
 {
-	unsigned long rid;
+	msg_rid_t rid;
 	int err;
 
 	do {
diff --git a/usb/usb.c b/usb/usb.c
index cc4cc13..cc960c1 100644
--- a/usb/usb.c
+++ b/usb/usb.c
@@ -253,7 +253,7 @@ static void usb_statusthr(void *arg)
 static void usb_msgthr(void *arg)
 {
 	unsigned port = (int)arg;
-	unsigned long rid;
+	msg_rid_t rid;
 	msg_t msg;
 	usb_msg_t *umsg;
 	int resp;