You can try this exercise to test whether or not your J2EE web application server is fully compatible with CICS.
By default, the EJB Bank Account sample is not configured to use distributed transactions. However, you can change this. The SampleServlet servlet contains sample code, which has been commented-out, to turn on client-demarcated transactions. (The SampleServlet.java source file is in the CicsSample.ear file.)
If you set up the sample to use client-demarcated transactions but your J2EE web application server does not support (or is not configured to use) pure OTS transactions, when you run the sample CICS throws an org.omg.CORBA.INVALID_TRANSACTION exception. This is because a transaction context was sent but CICS could not use it.