In 3.5, if you separate any part of a polymorphed creature's body, that part reverts to its original form. This ruling prevents you from (for example) polymorphing someone into a wyvern and extracting the vemom. It also prevents you from polymorphing into someone rich and then spending the money.
I don't think any interpretation of this spell can allow infinite uses of consumable magic items -- that would quickly break the game.
We might speculate about whether consuming your polymorph-duplicated items harms your original form -- like, did you just destroy the piece of you (or of your equipment) that polymorph-duplicated into that potion? But this restriction would be pretty easy to circumvent, so I don't think it's a fruitful avenue to pursue.
I like dark wanderer's interpretation that you get "the form of the creature when it lived" including its typical equipment loadout. But I would propose a second interpretation: you get the use of the corpse's magic items as long as they are still equipped on the corpse. If you take the plate mail off the corpse, then the corpse's equipment no longer includes a plate mail, so you don't get that when polymorphing any more. Using this interpretation, we could also allow consumable magic items, with the catch that consuming your copy of a magic item also consumes the corpse's copy.
Third interpretation: How much of the corpse did you consume when casting the spell? Were you magically able to consume all of it? If so, I'll bet you consumed the equipment as well. Any magical equipment you consumed, you can now generate when taking that form. If you ate a scroll when casting the spell, you can generate that scroll when taking that form, until you read the scroll. Once you've read the scroll, you can't generate copies of it any more.