I'm using the latest Zen Cart, with PPEC and the latest patch, with the USPS shipping module. When looking at the checkout screens, the tax isn't labeled. So it looks something like this:

Sub-Total: $x.xx

$x.xx [this is the tax that is unlabeled)

United States Postal Service (First-Class Mail (2 - 5 days)):
$x.xx


Total:$x.xx

Which file should I be looking in to correct this?