[HtmlUnit] Exception on JavaScript-Execution (onChange)

[<th...@cy...>]

Hi, 

it's me again. You told me before, that JavaScript-support should work
completely transparent. For example, if I choose an option of a
select-formfield, HtmlUnit should automatically fire up the
JavaScript-code stored in the onChange-attribute. Well, it doesn't.
Below you'll find some code-fragments and the stacktrace. If there is
any more I can do, to help you to degbug this, please let me know. 

The JavaScript stored in the onChange-attribute:
onChange="form.target='_self'; if
(options[selectedIndex].value.indexOf('|') >= 0)
{form.target=options[selectedIndex].value.split('|')[1];}
form.submit();"

The option-values look something like this: "view_object|_self"

The form includes some more JavaScript. Allthough I don't think it has
any influences on that bug, I'll send it to you anyways:
<script type="text/javascript">
<!--
document.write('<input type="hidden" name="navigator-vi-menu-cf-go"
value="go">');
// -->
</script>

There is also a noscript-part to it, which just contains the button
again (but type="submit"). See my mail before ;)

And that is the exception I get:

======= EXCEPTION START ========
EcmaError: lineNumber=[1] column=[0] lineSource=[GargoyleWrapper0()]
name=[TypeError] sourceName=[Wrapper definition for onChange handler]
message=[Cannot convert null to an object.] errorObject=[TypeError:
Cannot convert null to an object.]
com.gargoylesoftware.htmlunit.ScriptException: Cannot convert null to an
object.
        at
com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:199)
        at
com.gargoylesoftware.htmlunit.html.HtmlPage.executeJavaScriptIfPossible(HtmlPage.java:764)
        at
com.gargoylesoftware.htmlunit.html.HtmlSelect.setSelectedAttribute(HtmlSelect.java:142)
        at webtester.Menu.executeSelect(Menu.java:62)
        at webtester.Menu.selectOption(Menu.java:53)
        at npsGuiTests.SimpleTest.objectCreate(SimpleTest.java:70)
        at npsGuiTests.SimpleTest.runTest(SimpleTest.java:21)
        at npsGuiTests.RunTests.main(RunTests.java:17)
Enclosed exception:
TypeError: Cannot convert null to an object. (Wrapper definition for
onChange handler; line 1)
        at
org.mozilla.javascript.NativeGlobal.constructError(NativeGlobal.java:597)
        at
org.mozilla.javascript.NativeGlobal.constructError(NativeGlobal.java:557)
        at
org.mozilla.javascript.NativeGlobal.typeError0(NativeGlobal.java:562)
        at
org.mozilla.javascript.ScriptRuntime.setProp(ScriptRuntime.java:840)
        at org.mozilla.javascript.gen.c11.call(Wrapper definition for
onChange handler:1)
        at
org.mozilla.javascript.optimizer.OptRuntime.callSimple(OptRuntime.java:275)
        at org.mozilla.javascript.gen.c13.call(onChange handler:1)
        at org.mozilla.javascript.gen.c13.exec(onChange handler)
        at
org.mozilla.javascript.Context.evaluateReader(Context.java:820)
        at
org.mozilla.javascript.Context.evaluateString(Context.java:784)
        at
com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:191)
        at
com.gargoylesoftware.htmlunit.html.HtmlPage.executeJavaScriptIfPossible(HtmlPage.java:764)
        at
com.gargoylesoftware.htmlunit.html.HtmlSelect.setSelectedAttribute(HtmlSelect.java:142)
        at webtester.Menu.executeSelect(Menu.java:62)
        at webtester.Menu.selectOption(Menu.java:53)
        at npsGuiTests.SimpleTest.objectCreate(SimpleTest.java:70)
        at npsGuiTests.SimpleTest.runTest(SimpleTest.java:21)
        at npsGuiTests.RunTests.main(RunTests.java:17)
== CALLING JAVASCRIPT ==
GargoyleWrapper0()
======= EXCEPTION END ========

If I may priorize the bugs a bit, I'd prefer you to help me with the bug
reported before (<noscript>). JavaScript has not a major level of
importance in my tests. 

kind regards, 
Thomas Bartz
Berlin