Incorporated setAssociationTargetClass, which solves biggest problem of modular system in ZF. Any questions, pelase forward to @EvanDotPro.

lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php

@@ -1849,6 +1849,21 @@ class ClassMetadataInfo implements ClassMetadata
         }
     }
 
+    /**
+     * Refine an association targetEntity class pointer to be consumed through loadMetadata event.
+     *
+     * @param string $assoc
+     * @param string $class
+     */
+    public function setAssociationTargetClass($assocName, $class)
+    {
+        if ( ! isset($this->associationMappings[$assocName])) {
+            throw new \InvalidArgumentException("Association name expected, '" . $assocName ."' is not an association.");
+        }
+
+        $this->associationMappings[$assocName]['targetEntity'] = $class;
+    }
+
     /**
      * Sets whether this class is to be versioned for optimistic locking.
      *