diff --git a/ChangeLog b/ChangeLog
index ff6de0a9c6..643a4da029 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Mon Jan 19 11:22:51 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* ext/socket/rubysocket.h (rb_cUNIXSocket, rb_cUNIXServer),
+	  (unixpath, unixaddr): UNIX domain sockets depend on sys/un.h.
+
 Mon Jan 19 11:02:30 2009  Koichi Sasada  <ko1@atdot.net>
 
 	* vm_dump.c: add a prefix "rb_vmdebug_" to
diff --git a/ext/socket/rubysocket.h b/ext/socket/rubysocket.h
index bb2f6a6896..365eab63da 100644
--- a/ext/socket/rubysocket.h
+++ b/ext/socket/rubysocket.h
@@ -129,7 +129,7 @@ extern VALUE rb_cIPSocket;
 extern VALUE rb_cTCPSocket;
 extern VALUE rb_cTCPServer;
 extern VALUE rb_cUDPSocket;
-#ifdef AF_UNIX
+#ifdef HAVE_SYS_UN_H
 extern VALUE rb_cUNIXSocket;
 extern VALUE rb_cUNIXServer;
 #endif
@@ -177,8 +177,10 @@ VALUE make_ipaddr(struct sockaddr *addr);
 VALUE ipaddr(struct sockaddr *sockaddr, int norevlookup);
 VALUE make_hostent(VALUE host, struct addrinfo *addr, VALUE (*ipaddr)(struct sockaddr *, size_t));
 
+#ifdef HAVE_SYS_UN_H
 const char* unixpath(struct sockaddr_un *sockaddr, socklen_t len);
 VALUE unixaddr(struct sockaddr_un *sockaddr, socklen_t len);
+#endif
 
 int ruby_socket(int domain, int type, int proto);
 VALUE init_sock(VALUE sock, int fd);