LOL, boy do I feel stupid. I thought there must be some really cool feature in Dreamweaver that I didn't know about, never thinking about what you really said.
request:
<p class="eC_OrderInfo">API=RateV3&XML=<RateV3Request USERID="421BABXX6206"><Package ID="0"><Service>PARCEL</Service><ZipOrigination>94598</ZipOrigination><ZipDestination>94598</ZipDestination><Pounds>0</Pounds><Ounces>13</Ounces><Size>REGULAR</Size></Package></RateV3Request> </p>
So the machinable value is never being sent, hence the error. Are you aware of a variable or some such that I missed?
The eCart USPS Shipping server behavior is set to "Package machinable True" but it isn't being put into the response for some reason??
behavior jpg attached.