diff --git a/sys/net/ethernet.h b/sys/net/ethernet.h
index c5b61187268c..9db90a524b49 100644
--- a/sys/net/ethernet.h
+++ b/sys/net/ethernet.h
@@ -386,7 +386,7 @@ extern	int  ether_output_frame(struct ifnet *, struct mbuf *);
 extern	char *ether_sprintf(const u_int8_t *);
 void	ether_vlan_mtap(struct bpf_if *, struct mbuf *,
 	    void *, u_int);
-struct mbuf  *ether_vlanencap(struct mbuf *, int);
+struct mbuf  *ether_vlanencap(struct mbuf *, uint16_t);
 
 #else /* _KERNEL */
 
diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index 9509eb560ab0..a06a6cda5147 100644
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -1250,7 +1250,7 @@ ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen)
 }
 
 struct mbuf *
-ether_vlanencap(struct mbuf *m, int tag)
+ether_vlanencap(struct mbuf *m, uint16_t tag)
 {
 	struct ether_vlan_header *evl;