I see that this issue was previously marked as fixed: http://framework.zend.com/issues/browse/ZF-722

However, ZF 1.10.2 doesn't allow object methods. Source shows that private function _makeId($name, $parameters) still requires a string preventing object methods being specified in $cache->call()

 
/**
 * Make a cache id from the function name and parameters
 *
 * @param  string $name       Function name
 * @param  array  $parameters Function parameters
 * @throws Zend_Cache_Exception
 * @return string Cache id
 */
private function _makeId($name, $parameters)
{
    if (!is_string($name)) {
        Zend_Cache::throwException('Incorrect function name');
    }
    if (!is_array($parameters)) {
        Zend_Cache::throwException('parameters argument must be an array');
    }
    return md5($name . serialize($parameters));
}