We experienced the same problem when we upgraded to WebSphere 6.1 FP 24 for z/os.  We were running Drools 4.0.4 at the time.  I don't recall all the jar dependency versions, but we didn't change mvel from whatever Drools 4.0.4 came packaged with.  After some testing, we found that Drools 5.0.1 did not exhibit the same problem.  Fortunately, upgrading was an option for us and we've been running fine since. 
 
I noticed that the catch-all test for ValueType.OBJECT_TYPE in ValueType.determineValueType changed from an instanceof test in 4.0.4 to an Object.class.isAssignableFrom test in 5.0.1.  I wondered if a classloader issue caused a difference in the way to two tests were performed, though I didn't have time to investigate the theory.
 
Regards,
 
 
Rick
 
On 6/12/09, Corneil du Plessis <corneil@tsctech.com> wrote:



Edson Tirelli-3 wrote:
>
>    Ok, I saw this problem raised a couple times and it seems to be related
> with the JVM, not really the app server. It is a classloader problem.
>
>    Unfortunately, I could not reproduce this in my environment, so if
> anyone
> capable of reproducing the problem is willing to work with me on this, we
> can look for a solution. First of all, I need the complete stack trace of
> the problem, as well as drools version, mvel version, complete JVM version
> and revision. Then, it would be good if you can isolate the problem in a
> small test case, otherwise we will have to go without it for now.
>
>    Having that information, I will try to make some code changes and send
> you and see what happens.
>
>    Thank you,
>        Edson
>
>
>
> 2009/6/12 Corneil du Plessis <corneil@tsctech.com>
>
>>
>>
>> Srithu wrote:
>> >
>> > I have a wired behavior..
>> >
>> > I have a set of rules and i have used drools-guvnor to packaging
>> them...
>> > It is working in windows machines where i have jboss which is running
>> on
>> > IBM java 5 and 6..
>> >
>> > When i connect the same from  jboss Which is running on 64 bit IBM java
>> 6
>> > on linux is not working...
>> > The same is working If i used 64 bit IBM java 5 on linux.....
>> >
>> >
>> > I getting following exception...
>> >
>> >
>> >
>> > Please help....
>> >
>> >>> [2009-02-11 12:30:29,697] [705980] [http-0.0.0.0-8080-12] [ERROR]
>> >>> [STDERR ] - org.drools.RuntimeDroolsException: unable to determine
>> >>> ValueType for Class [class java.lang.Object]
>> >
>> >>> [2009-02-11 12:30:29,698] [705981] [http-0.0.0.0-8080-12] [ERROR]
>> >>> [STDERR ] -         at
>> >>> org.drools.base.ValueType.determineValueType(ValueType.java:193)
>> >
>> >>> [2009-02-11 12:30:29,698] [705981] [http-0.0.0.0-8080-12] [ERROR]
>> >>> [STDERR ] -         at
>> >>> org.drools.base.ValueType.readResolve(ValueType.java:125)
>> >
>> >>> [2009-02-11 12:30:29,698] [705981] [http-0.0.0.0-8080-12] [ERROR]
>> >>> [STDERR ] -         at
>> >>> sun.reflect.GeneratedMethodAccessor121.invoke(Unknown Source)
>> >
>> >>> [2009           -02-11 12:30:29,698] [705981] [http-0.0.0.0-8080-12]
>> >>> [ERROR] [STDERR ] -         at
>> >>>
>> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37)
>> >
>> >>> [2009-02-11 12:30:29,698] [705981] [http-0.0.0.0-8080-12] [ERROR]
>> >>> [STDERR ] -         at
>> java.lang.reflect.Method.invoke(Method.java:599)
>> >
>> > [deleted stacktrace]
>> >
>> >
>> We are experiencing same issue on WebSphere 6.1 FP 23 on Linux and AIX.
>> Has anyone found a resolution?
>>
>> Regards
>>
>> Corneil
>>
>> --
>> View this message in context:
>> http://www.nabble.com/unable-to-determine-value-type-class--***-URGENT***-tp21950333p24000218.html
>> Sent from the drools - user mailing list archive at Nabble.com.
>>
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>>
>
>
>
> --
>  Edson Tirelli
>  JBoss Drools Core Development
>  JBoss, a division of Red Hat @ www.jboss.com
>
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> rules-users mailing list
> rules-users@lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
>
>

I am sure it is not a Drools problem because everything worked fine on
WebSphere 6.1 FP 17 and 21 but with FP 23 the problem started.
We did raise an issue with IBM to see if it is possible to find a solution.
--
View this message in context: http://www.nabble.com/unable-to-determine-value-type-class--***-URGENT***-tp21950333p24005424.html
Sent from the drools - user mailing list archive at Nabble.com.

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