diff --git a/jerry-core/parser/js/jsp-early-error.cpp b/jerry-core/parser/js/jsp-early-error.cpp
index ebab430c4..aaf9a7d76 100644
--- a/jerry-core/parser/js/jsp-early-error.cpp
+++ b/jerry-core/parser/js/jsp-early-error.cpp
@@ -235,30 +235,29 @@ jsp_early_error_check_for_eval_and_arguments_in_strict_mode (operand op, bool is
 void
 jsp_early_error_check_for_syntax_errors_in_formal_param_list (bool is_strict, locus loc __attr_unused___)
 {
-  if (STACK_SIZE (props) - STACK_TOP (size_t_stack) < 2 || !is_strict)
+  if (is_strict
+      && STACK_SIZE (props) - STACK_TOP (size_t_stack) >= 2)
   {
-    STACK_DROP (size_t_stack, 1);
-    return;
-  }
-  for (size_t i = (STACK_TOP (size_t_stack) + 1u); i < STACK_SIZE (props); i++)
-  {
-    JERRY_ASSERT (STACK_ELEMENT (props, i).type == VARG);
-    literal_t previous = STACK_ELEMENT (props, i).lit;
-    JERRY_ASSERT (previous->get_type () == LIT_STR_T
-                  || previous->get_type () == LIT_MAGIC_STR_T
-                  || previous->get_type () == LIT_MAGIC_STR_EX_T);
-    for (size_t j = STACK_TOP (size_t_stack); j < i; j++)
+    for (size_t i = (STACK_TOP (size_t_stack) + 1u); i < STACK_SIZE (props); i++)
     {
-      JERRY_ASSERT (STACK_ELEMENT (props, j).type == VARG);
-      literal_t current = STACK_ELEMENT (props, j).lit;
-      JERRY_ASSERT (current->get_type () == LIT_STR_T
-                    || current->get_type () == LIT_MAGIC_STR_T
-                    || current->get_type () == LIT_MAGIC_STR_EX_T);
-      if (lit_literal_equal_type (previous, current))
+      JERRY_ASSERT (STACK_ELEMENT (props, i).type == VARG);
+      literal_t previous = STACK_ELEMENT (props, i).lit;
+      JERRY_ASSERT (previous->get_type () == LIT_STR_T
+                    || previous->get_type () == LIT_MAGIC_STR_T
+                    || previous->get_type () == LIT_MAGIC_STR_EX_T);
+      for (size_t j = STACK_TOP (size_t_stack); j < i; j++)
       {
-        PARSE_ERROR_VARG (JSP_EARLY_ERROR_SYNTAX,
-                          "Duplication of literal '%s' in FormalParameterList is not allowed in strict mode",
-                          loc, lit_literal_to_str_internal_buf (previous));
+        JERRY_ASSERT (STACK_ELEMENT (props, j).type == VARG);
+        literal_t current = STACK_ELEMENT (props, j).lit;
+        JERRY_ASSERT (current->get_type () == LIT_STR_T
+                      || current->get_type () == LIT_MAGIC_STR_T
+                      || current->get_type () == LIT_MAGIC_STR_EX_T);
+        if (lit_literal_equal_type (previous, current))
+        {
+          PARSE_ERROR_VARG (JSP_EARLY_ERROR_SYNTAX,
+                            "Duplication of literal '%s' in FormalParameterList is not allowed in strict mode",
+                            loc, lit_literal_to_str_internal_buf (previous));
+        }
       }
     }
   }
diff --git a/tests/jerry/regression-test-issue-381.js b/tests/jerry/regression-test-issue-381.js
new file mode 100644
index 000000000..701d533b7
--- /dev/null
+++ b/tests/jerry/regression-test-issue-381.js
@@ -0,0 +1,22 @@
+// Copyright 2015 Samsung Electronics Co., Ltd.
+// Copyright 2015 University of Szeged.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+function f_0(){
+    'use strict';
+    var v_0 = {
+        p_0: function(a_0, a_1) {}
+    };
+    f_1(function(a_2) {});
+}
diff --git a/tests/jerry/strict.js b/tests/jerry/strict.js
index 3e701f25f..0af967367 100644
--- a/tests/jerry/strict.js
+++ b/tests/jerry/strict.js
@@ -69,3 +69,8 @@ try
 {
   assert (e instanceof TypeError);
 }
+
+(function (a) {
+  (function (a) {
+  });
+});