diff --git a/ChangeLog b/ChangeLog
index 460ac8547b..7fc99b7913 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Jan  8 00:26:35 2009  Tanaka Akira  <akr@fsij.org>
+
+	* ext/socket/socket.c (addrinfo_getnameinfo): use NI_DGRAM if socktype
+	  is SOCK_DGRAM.
+
 Thu Jan  8 00:16:22 2009  Tanaka Akira  <akr@fsij.org>
 
 	* ext/socket/socket.c (host_str): add flags_ptr argument to specify
diff --git a/ext/socket/socket.c b/ext/socket/socket.c
index 49bd7503c5..aa959aa4e9 100644
--- a/ext/socket/socket.c
+++ b/ext/socket/socket.c
@@ -4491,6 +4491,9 @@ addrinfo_getnameinfo(int argc, VALUE *argv, VALUE self)
 
     flags = NIL_P(vflags) ? 0 : NUM2INT(vflags);
 
+    if (rai->socktype == SOCK_DGRAM)
+        flags |= NI_DGRAM;
+
     error = getnameinfo((struct sockaddr *)&rai->addr, rai->sockaddr_len,
                         hbuf, sizeof(hbuf), pbuf, sizeof(pbuf),
                         flags);