Hi, I don't think you have 2003SE. The latest upgrade from o2 is still 2003 (first edition). There is no official SE upgrade for the xdaII. However, I have recently upgraded using finalzero's 2003SE ROM available here and, as they say in glasgow, "it's pure minted, man". Highly recommended. Plus, I have been able to install it without the caller ID which makes the system a lot l-o-t slower. The extended ROM, by a fortuitous mistake, has to be installed manually so this can be customised.
Hope this helps.