diff --git a/lib/libalias/alias.h b/lib/libalias/alias.h
index 9d1f75518878..033021d12a4d 100644
--- a/lib/libalias/alias.h
+++ b/lib/libalias/alias.h
@@ -157,5 +157,8 @@ extern u_short InternetChecksum(u_short *, int);
 #define PKT_ALIAS_UNRESOLVED_FRAGMENT 3
 #define PKT_ALIAS_FOUND_HEADER_FRAGMENT 4
 
+#undef __libalias_version
+#define __libalias_version "2.5"
+
 #endif
 /*lint -restore */
diff --git a/sys/netinet/libalias/alias.h b/sys/netinet/libalias/alias.h
index 9d1f75518878..033021d12a4d 100644
--- a/sys/netinet/libalias/alias.h
+++ b/sys/netinet/libalias/alias.h
@@ -157,5 +157,8 @@ extern u_short InternetChecksum(u_short *, int);
 #define PKT_ALIAS_UNRESOLVED_FRAGMENT 3
 #define PKT_ALIAS_FOUND_HEADER_FRAGMENT 4
 
+#undef __libalias_version
+#define __libalias_version "2.5"
+
 #endif
 /*lint -restore */