The only language I've seen related to carriers on the U-PIC policy was reference to "major" carrier. As far as I know, DHL is one of the 3 or 4 largest, along with Fedex and UPS, and the USPS.
Honestly can't imagine them not being covered.
If I'm wrong about that, or there's some restrictions on carriers, someone from Auctiva give a SHOUT!
Danno