2005FPW Service Tag

In order to contact technical support to I need a service tag, but I can't seem to find a service tag on the back of my screen.

Obviously I find the sticker with three numbers, a date of production, a revision id and a longer tag with both letters and numbers. However, none of them are accepted as a service tag.

Here's a pic of the sticker:

If someone could tell me how I can derive the service tag or where to find it I'd be most obliged.

Thanks in advance.