You can't charge via USB but you can get a cable that converts power from USB to the dc input, check the Coby Gen 2 Acessories thread about it. It mentions a 7022 but should work for 7127 as well since it also has a 5V input dc (just make sure the power supply can provide the minimum number of amperes needed).
THANK YOU IFOM!!! Just what I've been needing...