USPS shipping - overcharging??

I have been using the USPS shipping module since I moved to Zen Cart last year and so far it has worked fine...until today. I just noticed an order that came in overnight that seemed to have a higher cost of shipping on it. I ship all my items via Priority Mail and this particular item is rated at 1 lb. which should come up as $4.05 (well, I add $0.80 for handling, so $4.85). This one came up as $6.85.

I ship out of New York and the item was going to California...however, that shouldn't matter at all because Priority Mail is a flat fee for anything 1 lb. and under. I tried another California address and sure enough, it comes up as $6.85. Did something change recently? I have not altered my settings so I don't know what could have happeend.

The weird thing is that it seems to show correct shipping for my local address so I don't think it has been affected by all areas. Also, I checked the shipping charges on the USPS website for the zip code in California and it also shows up the correct price.

Anyone have the same problem?

EDIT: I am using version 1.2.X...I forget which release exactly, but it's the one right before 1.3. I also see a thread on a new USPS shipping module...will this solve my problem?

I'll bet the product came in at just over 1 lb. That would account for the New York to LA cost of 6.05 + .80 = 6.85

Not sure how it could have come in over a pund...the item is set at exactly 1 lb. and I don't add any extra.

The weird thing is that it seemed to have fixed itself...I just tried it again with the same address and it works fine. I wonder if it was some glitch in the USPS server?

Did yu check in the Shipping/Packaging for the Tare weight on the packages for your boxing and bubblewrap?

Yeah, I checked all that and it was thje way Ihad it set up before. I think I solved it though. I sell t-shirts and I usually set up my products for a half pound...but I accidentally set up some new products as exactly a pound. Since the Priority Mail charges go up after a pound, it might have just been a little glitch in the server or the way it processed it. I set everything back to a half pound and it works now...whew!