adding class members in C

Hi, I'm trying to write a class as a PHP C extension. I want to add a member variable to class declaration time. I believe this is possible by adding to the zend_class_entry's default_properties HashTable. My attempts so far have resulted in apache core dumps. My code for PHP_MINIT_FUNCTION look like: zend_class_entry MyClass_class_entry; char *cv2; INIT_CLASS_ENTRY(MyClass_class_entry, "MyClass", MyClass_class_funcs); MyClass_class_entry_ptr = zend_register_internal_class(&MyClass_class_entry); fprintf(stderr,"Registered class with name '%s'\n",MyClass_class_entry_ptr->name); zend_hash_update(&MyClass_class_entry_ptr->default_properties, "memvar", 7, "member value", 13, (void **) &cv2); fprintf(stderr,"made MyClass::memvar point to '%s'\n", cv2); However, I get coredumps on apache startup. What is the correct way to register member variables at class declaration time? thanks dave