diff --git a/pjlib/src/pj/sock_bsd.c b/pjlib/src/pj/sock_bsd.c
index eb6db13..9cc4abb 100644
--- a/pjlib/src/pj/sock_bsd.c
+++ b/pjlib/src/pj/sock_bsd.c
@@ -64,6 +64,8 @@
 const pj_uint16_t PJ_SOL_TCP	= SOL_TCP;
 #elif defined(IPPROTO_TCP)
 const pj_uint16_t PJ_SOL_TCP	= IPPROTO_TCP;
+#else
+const pj_uint16_t PJ_SOL_TCP	= 0xFFFF;
 #endif /* SOL_TCP */
 #ifdef SOL_UDP
 const pj_uint16_t PJ_SOL_UDP	= SOL_UDP;