Early MCF5208 devices are marked as M28B mask set. The latest version of the MCF520x is marked as 2M28B.
MCF5208 Chip Errata Silicon Revision: All, Supports: MCF5207 and MCF5208 - Errata
Early MCF5208 devices are marked as M28B mask set. The latest version of the MCF520x is marked as 2M28B.