About integrating MathML
When IXIASOFT integrated MathML into previous versions of the DITA CMS, the integration was based on a non-final version of the DITA 1.3 specification. The final integration is very slightly different from the original IXIASOFT integration (which we will call the "beta" integration). Even if you have content that incorporates MathML that follows the beta integration, it might not be invalidated if you use the official DITA 1.3 integration. It is probably worth your while to test this content to see. If you can use the official integration, it will avoid additional maintenance and support issues that could arise from using a non-DITA 1.3-conformant configuration.
IXIASOFT does not have any test scripts for MathML. The simplest approach is probably to setup up a test system with the official integration and generate output for content that includes MathML markup. If the outputs are successful, then you know that your MathML is valid under the official DITA 1.3 integration. If you have a small amount of non-valid MathML, it is still probably worth your while to refactor it to be conformant with the DITA 1.3 specification rather than to move forward with DITA 1.3 while using the beta MathML integration.
Some older versions of the DITA CMS, such as 3.4, might be using a MathML implementation that is based on MathML2. (How can you tell? Look in system/dtd. If there are mathml2, mathml3 and mathmlDomain folders, it's possible you are using MathML2. Upgrading this implementation could be a bit trickier and content based on MathML2 might require additional refactoring. Contact IXIASOFT support for help.