Spring creates a DataOnDemand infrastructure (java/AspectJ) for creating and obtaining data in the integration tests. However, Roo "autowires" this object in the Aspect Integration test (XXXTest_Roo_IntegrationTest.aj) as a private variable, without getter. Thus, you can't access it from the Java Integration test (XXXTest.java)
If the "autowired" DataOnDemand (dod) were not private in the Roo Integration Test Aspect (IntegrationTest_Roo_IntegrationTest) it would be more easier to write your own tests and modifying the existing ones.
I know that I can copy this field to the Java class for doing so, but I've realized that the repository is "autowired" in the IntegrationTest_Roo_IntegrationTest file with package visibility (no modifier) and I wonder if Roo could give the same modifier to the DataOnDemand