diff --git a/src/unix/internal.h b/src/unix/internal.h
index 114cb696..d5bc3109 100644
--- a/src/unix/internal.h
+++ b/src/unix/internal.h
@@ -143,7 +143,7 @@ enum {
   UV_TCP_NODELAY          = 0x400,  /* Disable Nagle. */
   UV_TCP_KEEPALIVE        = 0x800,  /* Turn on keep-alive. */
   UV_TCP_SINGLE_ACCEPT    = 0x1000, /* Only accept() when idle. */
-  UV_HANDLE_IPV6          = 0x2000  /* Handle is bound to a IPv6 socket. */
+  UV_HANDLE_IPV6          = 0x10000 /* Handle is bound to a IPv6 socket. */
 };
 
 typedef enum {