Error, "Not Supported" when generating test data for a table with referenced tables (4227169)

I'm trying to use the Data Generator in Toad for DB2, but I'm getting a "Not Supported" type expception error. Then I get the error:

Object reference not set to an instance of an object.

The error only seems to occur for tables that have referenced tables in different schemas.

1. Right-click a table in the Object Explorer and select Generate Test Data.
2. Click on the Add Referenced button.
3. Click on Next and then click on Next on the Options page.
4. Click on Next on the Customize page and then the crash occurs.