Are you sure it's actually a
Sony Ericsson? Ericsson were making phones long before they merged with Sony, and I think that is one of those older phones. In that case you won't have much luck finding your model on the SE site.
EDIT: It's the Ericsson T68,
later known as Sony Ericsson T68i.
Here is a image of it, and I would say it's a match?
EDIT2: According to Wikipedia, it has Bluetooth =/ Mabye that is only on the updated SE one?
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