Here's the problem with that rebate form.
It shows L01J030 as being the model alongside ALL the drives. The 30, 40, 60, and 80.
The 40GB is model L01J040, the 60 is J060, and so on. So, person doing the fulfillment probably looked at your 80GB upc which would have showed L01J080, and said "no, that does't match, it's supposed to be L01J030 according to the top of the rebate form"
If you call Maxtor, THAT'S the problem. Call up again, get them to go to that URL, if they even know their own products they should IMMEDIATELY know that all 4 models have 4 different model numbers ( a duh ) and they end in 30, 40, 60 or 80 respectively for the 30, 40, 60, or 80 GB models, and that their rebate form has this all screwed up.
Otherwise, you can call staples rebate center, they CAN validate this rebate, especially since they're hosting the form that has the incorrect ( ie same ) model for all 4 unique drive products/models.
Christ...I don't even work for this company and I can spot this error right off, can't they get simple stuff like this straight before they give such a form to staples?