diff --git a/ChangeLog b/ChangeLog
index bcd85c7392..ae12222e64 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+Mon Feb  9 23:04:27 2009  Tanaka Akira  <akr@fsij.org>
+
+	* ext/socket/mkconstants.rb: rename level_to_int to iplevel_to_int.
+	  rename intern_level to intern_iplevel.
+
+	* ext/socket/constants.c: follow the renaming.
+
+	* ext/socket/option.c: ditto.
+
+	* ext/socket/ancdata.c: ditto.
+
 Mon Feb  9 22:52:13 2009  Tanaka Akira  <akr@fsij.org>
 
 	* ext/socket/rubysocket.h (level_arg): add family argument.
diff --git a/ext/socket/ancdata.c b/ext/socket/ancdata.c
index 06ec546646..27b15b25fc 100644
--- a/ext/socket/ancdata.c
+++ b/ext/socket/ancdata.c
@@ -605,7 +605,7 @@ ancillary_inspect(VALUE self)
     else
         rb_str_catf(ret, "family:%d", family);
 
-    level_id = intern_level(level);
+    level_id = intern_iplevel(level);
     if (level_id)
         rb_str_catf(ret, " %s", rb_id2name(level_id));
     else
diff --git a/ext/socket/constants.c b/ext/socket/constants.c
index 3b7906f890..aaedfa1962 100644
--- a/ext/socket/constants.c
+++ b/ext/socket/constants.c
@@ -61,7 +61,7 @@ int
 level_arg(int family, VALUE level)
 {
     /* convert SOL_SOCKET, IPPROTO_TCP, etc. */
-    return constant_arg(level, level_to_int, "unknown protocol level");
+    return constant_arg(level, iplevel_to_int, "unknown protocol level");
 }
 
 int
diff --git a/ext/socket/mkconstants.rb b/ext/socket/mkconstants.rb
index 5aa00b9b2b..30cc90d47a 100644
--- a/ext/socket/mkconstants.rb
+++ b/ext/socket/mkconstants.rb
@@ -242,7 +242,7 @@ end
 def_name_to_int("family_to_int", /\A(AF_|PF_)/, "AF_")
 def_name_to_int("socktype_to_int", /\ASOCK_/, "SOCK_")
 def_name_to_int("ipproto_to_int", /\AIPPROTO_/, "IPPROTO_")
-def_name_to_int("level_to_int", /\A(SOL_SOCKET\z|IPPROTO_)/, /\A(SOL_|IPPROTO_)/)
+def_name_to_int("iplevel_to_int", /\A(SOL_SOCKET\z|IPPROTO_)/, /\A(SOL_|IPPROTO_)/)
 def_name_to_int("so_optname_to_int", /\ASO_/, "SO_")
 def_name_to_int("ip_optname_to_int", /\AIP_/, "IP_")
 def_name_to_int("ipv6_optname_to_int", /\AIPV6_/, "IPV6_", "IPPROTO_IPV6")
@@ -255,7 +255,7 @@ def_intern('intern_family',  /\AAF_/)
 def_intern('intern_protocol_family',  /\APF_/)
 def_intern('intern_socktype',  /\ASOCK_/)
 def_intern('intern_ipproto',  /\AIPPROTO_/)
-def_intern('intern_level',  /\A(SOL_SOCKET\z|IPPROTO_)/, /\A(SOL_|IPPROTO_)/)
+def_intern('intern_iplevel',  /\A(SOL_SOCKET\z|IPPROTO_)/, /\A(SOL_|IPPROTO_)/)
 def_intern('intern_so_optname',  /\ASO_/, "SO_")
 def_intern('intern_ip_optname',  /\AIP_/, "IP_")
 def_intern('intern_ipv6_optname',  /\AIPV6_/, "IPV6_")
diff --git a/ext/socket/option.c b/ext/socket/option.c
index e09cb79ae5..c0e28b7c3a 100644
--- a/ext/socket/option.c
+++ b/ext/socket/option.c
@@ -318,7 +318,7 @@ sockopt_inspect(VALUE self)
 	    rb_str_catf(ret, " optname:%d", optname);
     }
     else {
-	level_id = intern_level(level);
+	level_id = intern_iplevel(level);
 	if (level_id)
 	    rb_str_catf(ret, " %s", rb_id2name(level_id));
 	else