diff --git a/qse/lib/awk/parse.c b/qse/lib/awk/parse.c
index a8f12c23..409a3ca9 100644
--- a/qse/lib/awk/parse.c
+++ b/qse/lib/awk/parse.c
@@ -1,5 +1,5 @@
 /*
- * $Id: parse.c 215 2009-06-27 05:52:54Z hyunghwan.chung $
+ * $Id: parse.c 216 2009-06-27 12:42:53Z hyunghwan.chung $
  *
    Copyright 2006-2009 Chung, Hyung-Hwan.
 
@@ -845,7 +845,8 @@ static qse_awk_nde_t* parse_function (qse_awk_t* awk)
 		return QSE_NULL;
 	}
 
-	if (qse_map_search (awk->tree.funs, name, name_len) != QSE_NULL) 
+	/* check if it has already been defined as a function */
+	if (qse_map_search (awk->tree.funs, name, name_len) != QSE_NULL)
 	{
 		/* the function is defined previously */
 		SETERRARG (
@@ -854,6 +855,15 @@ static qse_awk_nde_t* parse_function (qse_awk_t* awk)
 		return QSE_NULL;
 	}
 
+	/* check if it conflicts with a named variable */
+	if (qse_map_search (awk->parse.named, name, name_len) != QSE_NULL)
+	{
+		SETERRARG (
+			awk, QSE_AWK_EVARRED, awk->token.line, 
+			name, name_len);
+		return QSE_NULL;
+	}
+
 	/* check if it coincides to be a global variable name */
 	g = find_global (awk, name, name_len);
 	if (g != QSE_LDA_NIL)
diff --git a/qse/regress/awk/lang-002.awk b/qse/regress/awk/lang-002.awk
index 55bc7ad9..c548b89e 100644
--- a/qse/regress/awk/lang-002.awk
+++ b/qse/regress/awk/lang-002.awk
@@ -1,6 +1,6 @@
-function f(f)
+function f(x)
 {
-	print f;
+	print x;
 	f("my hello");
 }
 
diff --git a/qse/regress/awk/lang-003.awk b/qse/regress/awk/lang-003.awk
index 36b4ea59..f536bc7e 100644
--- a/qse/regress/awk/lang-003.awk
+++ b/qse/regress/awk/lang-003.awk
@@ -1,3 +1,3 @@
-# should print 50
-function fn(f) { f = 20; }
-BEGIN { f = 50; fn(100); print f; }
+# should print 50
+function fn(f) { f = 20; }
+BEGIN { f = 50; fn(100); print f; }
diff --git a/qse/regress/awk/lang-004.awk b/qse/regress/awk/lang-004.awk
index 93591f81..e5031a8c 100644
--- a/qse/regress/awk/lang-004.awk
+++ b/qse/regress/awk/lang-004.awk
@@ -1,3 +1,3 @@
 # A function and a named variable cannot have the same name.
-function a () { }
-BEGIN { a = 20; }
+function a () { }
+BEGIN { a = 20; }