Programmatically overriding "use share cache" fails

Using Cayenne 1.2.2, jdk5.

In the modeler under cache configuration the "use shared cache" is disabled. This value I want to override programatically for example:

boolean useSharedCache = true;
DataContext context = DataContext.createDataContext(useSharedCache);
DataObjectUtils.objectForPK(context, Employee.class, 200);

This throws a nullpointer. Stack trace below.

Is this valid use of the API?

If I enable the "use shared cache" in the modeler this works fine, so its not a big issue.

Stacktrace:

Exception in thread "main" java.lang.NullPointerException
at org.objectstyle.cayenne.access.DataDomainQueryAction.interceptOIDQuery(DataDomainQueryAction.java:166)
at org.objectstyle.cayenne.access.DataDomainQueryAction.execute(DataDomainQueryAction.java:143)
at org.objectstyle.cayenne.access.DataDomain.onQuery(DataDomain.java:766)
at org.objectstyle.cayenne.util.ObjectContextQueryAction.runQuery(ObjectContextQueryAction.java:253)
at org.objectstyle.cayenne.access.DataContextQueryAction.execute(DataContextQueryAction.java:90)
at org.objectstyle.cayenne.access.DataContext.onQuery(DataContext.java:1423)
at org.objectstyle.cayenne.access.DataContext.performQuery(DataContext.java:1412)
at org.objectstyle.cayenne.DataObjectUtils.objectForQuery(DataObjectUtils.java:290)
at org.objectstyle.cayenne.DataObjectUtils.objectForPK(DataObjectUtils.java:276)
at org.objectstyle.cayenne.DataObjectUtils.objectForPK(DataObjectUtils.java:167)
at test.CacheOverride.main(CacheOverride.java:20)

regards

bob