diff --git a/ChangeLog b/ChangeLog
index 6665794f7d..2cef209743 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Sun Sep  3 04:40:42 2006  Tanaka Akira  <akr@fsij.org>
+
+	* ext/socket/extconf.rb: check arpa/inet.h for ntohs.
+
+	* ext/socket/socket.c: include arpa/inet.h if available.
+
 Sun Sep  3 04:03:06 2006  Tanaka Akira  <akr@fsij.org>
 
 	* ext/curses/curses.c: define _XOPEN_SOURCE_EXTENDED on HP-UX.
diff --git a/ext/socket/extconf.rb b/ext/socket/extconf.rb
index 125ef6be20..1441dee4c0 100644
--- a/ext/socket/extconf.rb
+++ b/ext/socket/extconf.rb
@@ -25,6 +25,9 @@ if /solaris/ =~ RUBY_PLATFORM and !try_compile("")
   # bug of gcc 3.0 on Solaris 8 ?
   headers << "sys/feature_tests.h"
 end
+if have_header("arpa/inet.h")
+  headers << "arpa/inet.h"
+end
 
 ipv6 = false
 default_ipv6 = /cygwin/ !~ RUBY_PLATFORM
@@ -237,7 +240,6 @@ unless getaddr_info_ok and have_func("getnameinfo", "netdb.h") and have_func("ge
   have_func("inet_ntop") or have_func("inet_ntoa")
   have_func("inet_pton") or have_func("inet_aton")
   have_func("getservbyport")
-  have_header("arpa/inet.h")
   have_header("arpa/nameser.h")
   have_header("resolv.h")
 end
diff --git a/ext/socket/socket.c b/ext/socket/socket.c
index 8cc850b8a1..bb462f2fb3 100644
--- a/ext/socket/socket.c
+++ b/ext/socket/socket.c
@@ -41,6 +41,9 @@
 #ifdef HAVE_NETINET_UDP_H
 # include <netinet/udp.h>
 #endif
+#ifdef HAVE_ARPA_INET_H
+# include <arpa/inet.h>
+#endif
 #include <netdb.h>
 #endif
 #include <errno.h>