php - Using Doctrine Annotations with Zend Guard

I have just purchased Zend Guard in order to protect my application, ready for deployment. On attempting an install on the first customer site, it appears that our application encounters a fundamental error related to Doctrine.

Uncaught exception 'Doctrine\ORM\Mapping\MappingException' with message 'Class 
"Module\Entity\MyClass" sub class of "S2Common\Object\DoctrineObject" is not a 
valid entity or mapped super class.'
Copy code

(obviously I have altered the class name)

I am wondering if this is because we are using DocBlock Annotations in Doctrine and wondering whether these are either removed, or whether Doctrine is trying to read them directly, without engaging the Zend Guard Module.

Has anyone else had any experience of this? Is there a way to generate the cached metadata prior to deployment? I can't believe that this hasn't been thought out before...

Any help is appreciated