diff --git a/js/tests/ecma_3/Exceptions/15.11.7.6-001.js b/js/tests/ecma_3/Exceptions/15.11.7.6-001.js
new file mode 100644
index 00000000000..a8097f55a13
--- /dev/null
+++ b/js/tests/ecma_3/Exceptions/15.11.7.6-001.js
@@ -0,0 +1,125 @@
+/* ***** BEGIN LICENSE BLOCK *****
+* Version: NPL 1.1/GPL 2.0/LGPL 2.1
+*
+* The contents of this file are subject to the Netscape Public License
+* Version 1.1 (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.mozilla.org/NPL/
+*
+* Software distributed under the License is distributed on an "AS IS" basis,
+* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+* for the specific language governing rights and limitations under the
+* License.
+*
+* The Original Code is JavaScript Engine testing utilities.
+*
+* The Initial Developer of the Original Code is Netscape Communications Corp.
+* Portions created by the Initial Developer are Copyright (C) 2003
+* the Initial Developer. All Rights Reserved.
+*
+* Contributor(s): igor@fastmail.fm, pschwartau@netscape.com
+*
+* Alternatively, the contents of this file may be used under the terms of
+* either the GNU General Public License Version 2 or later (the "GPL"), or
+* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+* in which case the provisions of the GPL or the LGPL are applicable instead
+* of those above. If you wish to allow use of your version of this file only
+* under the terms of either the GPL or the LGPL, and not to allow others to
+* use your version of this file under the terms of the NPL, indicate your
+* decision by deleting the provisions above and replace them with the notice
+* and other provisions required by the GPL or the LGPL. If you do not delete
+* the provisions above, a recipient may use your version of this file under
+* the terms of any one of the NPL, the GPL or the LGPL.
+*
+* ***** END LICENSE BLOCK *****
+*
+*
+* Date:    14 April 2003
+* SUMMARY: Prototype of predefined error objects should be DontEnum
+* See http://bugzilla.mozilla.org/show_bug.cgi?id=201989
+*
+*/
+//-----------------------------------------------------------------------------
+var UBound = 0;
+var bug = 201989;
+var summary = 'Prototype of predefined error objects should be DontEnum';
+var status = '';
+var statusitems = [];
+var actual = '';
+var actualvalues = [];
+var expect= '';
+var expectedvalues = [];
+
+
+/*
+ * Tests that |F.prototype| is not enumerable in |F|
+ */
+function testDontEnum(F)
+{
+  var proto = F.prototype;
+
+  for (var prop in F)
+  {
+    if (F[prop] === proto)
+      return false;
+  }
+  return true;
+}
+
+
+var list = [
+    "Error",
+    "ConversionError",
+    "EvalError",
+    "RangeError",
+    "ReferenceError",
+    "SyntaxError",
+    "TypeError",
+    "URIError"
+];
+
+
+for (i in list)
+{
+  var F = this[list[i]];
+
+  // Test for |F|; e.g. Rhino defines |ConversionError| while SM does not.
+  if (F)
+  {
+    status = 'Testing DontEnum attribute of |' + list[i] + '.prototype|';
+    actual = testDontEnum(F);
+    expect = true;
+    addThis();
+  }
+}
+
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+
+
+function addThis()
+{
+  statusitems[UBound] = status;
+  actualvalues[UBound] = actual;
+  expectedvalues[UBound] = expect;
+  UBound++;
+}
+
+
+function test()
+{
+  enterFunc('test');
+  printBugNumber(bug);
+  printStatus(summary);
+
+  for (var i=0; i<UBound; i++)
+  {
+    reportCompare(expectedvalues[i], actualvalues[i], statusitems[i]);
+  }
+
+  exitFunc ('test');
+}
diff --git a/js/tests/ecma_3/Exceptions/15.11.7.6-002.js b/js/tests/ecma_3/Exceptions/15.11.7.6-002.js
new file mode 100644
index 00000000000..f0fae24b153
--- /dev/null
+++ b/js/tests/ecma_3/Exceptions/15.11.7.6-002.js
@@ -0,0 +1,120 @@
+/* ***** BEGIN LICENSE BLOCK *****
+* Version: NPL 1.1/GPL 2.0/LGPL 2.1
+*
+* The contents of this file are subject to the Netscape Public License
+* Version 1.1 (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.mozilla.org/NPL/
+*
+* Software distributed under the License is distributed on an "AS IS" basis,
+* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+* for the specific language governing rights and limitations under the
+* License.
+*
+* The Original Code is JavaScript Engine testing utilities.
+*
+* The Initial Developer of the Original Code is Netscape Communications Corp.
+* Portions created by the Initial Developer are Copyright (C) 2003
+* the Initial Developer. All Rights Reserved.
+*
+* Contributor(s): igor@fastmail.fm, pschwartau@netscape.com
+*
+* Alternatively, the contents of this file may be used under the terms of
+* either the GNU General Public License Version 2 or later (the "GPL"), or
+* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+* in which case the provisions of the GPL or the LGPL are applicable instead
+* of those above. If you wish to allow use of your version of this file only
+* under the terms of either the GPL or the LGPL, and not to allow others to
+* use your version of this file under the terms of the NPL, indicate your
+* decision by deleting the provisions above and replace them with the notice
+* and other provisions required by the GPL or the LGPL. If you do not delete
+* the provisions above, a recipient may use your version of this file under
+* the terms of any one of the NPL, the GPL or the LGPL.
+*
+* ***** END LICENSE BLOCK *****
+*
+*
+* Date:    14 April 2003
+* SUMMARY: Prototype of predefined error objects should be DontDelete
+* See http://bugzilla.mozilla.org/show_bug.cgi?id=201989
+*
+*/
+//-----------------------------------------------------------------------------
+var UBound = 0;
+var bug = 201989;
+var summary = 'Prototype of predefined error objects should be DontDelete';
+var status = '';
+var statusitems = [];
+var actual = '';
+var actualvalues = [];
+var expect= '';
+var expectedvalues = [];
+
+
+/*
+ * Tests that |F.prototype| is DontDelete
+ */
+function testDontDelete(F)
+{
+  var orig = F.prototype;
+  delete F.prototype;
+  return F.prototype === orig;
+}
+
+
+var list = [
+    "Error",
+    "ConversionError",
+    "EvalError",
+    "RangeError",
+    "ReferenceError",
+    "SyntaxError",
+    "TypeError",
+    "URIError"
+];
+
+
+for (i in list)
+{
+  var F = this[list[i]];
+
+  // Test for |F|; e.g. Rhino defines |ConversionError| while SM does not.
+  if (F)
+  {
+    status = 'Testing DontDelete attribute of |' + list[i] + '.prototype|';
+    actual = testDontDelete(F);
+    expect = true;
+    addThis();
+  }
+}
+
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+
+
+function addThis()
+{
+  statusitems[UBound] = status;
+  actualvalues[UBound] = actual;
+  expectedvalues[UBound] = expect;
+  UBound++;
+}
+
+
+function test()
+{
+  enterFunc('test');
+  printBugNumber(bug);
+  printStatus(summary);
+
+  for (var i=0; i<UBound; i++)
+  {
+    reportCompare(expectedvalues[i], actualvalues[i], statusitems[i]);
+  }
+
+  exitFunc ('test');
+}
diff --git a/js/tests/ecma_3/Exceptions/15.11.7.6-003.js b/js/tests/ecma_3/Exceptions/15.11.7.6-003.js
new file mode 100644
index 00000000000..5840427f6f1
--- /dev/null
+++ b/js/tests/ecma_3/Exceptions/15.11.7.6-003.js
@@ -0,0 +1,120 @@
+/* ***** BEGIN LICENSE BLOCK *****
+* Version: NPL 1.1/GPL 2.0/LGPL 2.1
+*
+* The contents of this file are subject to the Netscape Public License
+* Version 1.1 (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.mozilla.org/NPL/
+*
+* Software distributed under the License is distributed on an "AS IS" basis,
+* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+* for the specific language governing rights and limitations under the
+* License.
+*
+* The Original Code is JavaScript Engine testing utilities.
+*
+* The Initial Developer of the Original Code is Netscape Communications Corp.
+* Portions created by the Initial Developer are Copyright (C) 2003
+* the Initial Developer. All Rights Reserved.
+*
+* Contributor(s): igor@fastmail.fm, pschwartau@netscape.com
+*
+* Alternatively, the contents of this file may be used under the terms of
+* either the GNU General Public License Version 2 or later (the "GPL"), or
+* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+* in which case the provisions of the GPL or the LGPL are applicable instead
+* of those above. If you wish to allow use of your version of this file only
+* under the terms of either the GPL or the LGPL, and not to allow others to
+* use your version of this file under the terms of the NPL, indicate your
+* decision by deleting the provisions above and replace them with the notice
+* and other provisions required by the GPL or the LGPL. If you do not delete
+* the provisions above, a recipient may use your version of this file under
+* the terms of any one of the NPL, the GPL or the LGPL.
+*
+* ***** END LICENSE BLOCK *****
+*
+*
+* Date:    14 April 2003
+* SUMMARY: Prototype of predefined error objects should be ReadOnly
+* See http://bugzilla.mozilla.org/show_bug.cgi?id=201989
+*
+*/
+//-----------------------------------------------------------------------------
+var UBound = 0;
+var bug = 201989;
+var summary = 'Prototype of predefined error objects should be ReadOnly';
+var status = '';
+var statusitems = [];
+var actual = '';
+var actualvalues = [];
+var expect= '';
+var expectedvalues = [];
+
+
+/*
+ * Tests that |F.prototype| is ReadOnly
+ */
+function testReadOnly(F)
+{
+  var orig = F.prototype;
+  F.prototype = new Object();
+  return F.prototype === orig;
+}
+
+
+var list = [
+    "Error",
+    "ConversionError",
+    "EvalError",
+    "RangeError",
+    "ReferenceError",
+    "SyntaxError",
+    "TypeError",
+    "URIError"
+];
+
+
+for (i in list)
+{
+  var F = this[list[i]];
+
+  // Test for |F|; e.g. Rhino defines |ConversionError| while SM does not.
+  if (F)
+  {
+    status = 'Testing ReadOnly attribute of |' + list[i] + '.prototype|';
+    actual = testReadOnly(F);
+    expect = true;
+    addThis();
+  }
+}
+
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+
+
+function addThis()
+{
+  statusitems[UBound] = status;
+  actualvalues[UBound] = actual;
+  expectedvalues[UBound] = expect;
+  UBound++;
+}
+
+
+function test()
+{
+  enterFunc('test');
+  printBugNumber(bug);
+  printStatus(summary);
+
+  for (var i=0; i<UBound; i++)
+  {
+    reportCompare(expectedvalues[i], actualvalues[i], statusitems[i]);
+  }
+
+  exitFunc ('test');
+}