Not sure if this is Ninjalister only, or if it is Bulk Uploader too, however:
the limit is 13 Oz. not 3.5 Oz.Originally Posted by Bulk Uploads Error report
http://www.usps.com/prices/first-class-mail-prices.htmOriginally Posted by USPS
Same issue with International, however I don't know the weight limit offhand, so I'm not sure about that one.
**Update** didnt realize the system was so strictly checking for type (Letter Vs. Large Envelope Vs. Package, etc.. )
Never saw this problem with weight issues before - cause it's kinda tough to fit 3+ oz into a regular normal postal envelope unless you're shipping coins or something.. in which case, you'd be insane to try using a normal everyday envelope... Just another thing Ive gotta get used to, I guess