diff -uprN -X linux-2.6.18-vanilla/Documentation/dontdiff linux-2.6.18-vanilla/net/bridge/br_if.c linux-2.6.18/net/bridge/br_if.c
--- linux-2.6.18-vanilla/net/bridge/br_if.c	2006-09-20 05:42:06.000000000 +0200
+++ linux-2.6.18/net/bridge/br_if.c	2006-09-20 23:03:26.000000000 +0200
@@ -407,7 +407,8 @@ int br_add_if(struct net_bridge *br, str
 	struct net_bridge_port *p;
 	int err = 0;
 
-	if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER)
+	if (dev->flags & IFF_LOOPBACK ||
+	    dev->type != ARPHRD_ETHER && dev->type != ARPHRD_ETHERIP)
 		return -EINVAL;
 
 	if (dev->hard_start_xmit == br_dev_xmit)