Changing USB maximum current ouput

I'm working on a project based on the EasyLogger project. My interface works great, but the sensor I'm attempting to power requires around 120mA. The total current requirement for my circuit is around 140mA. The problem, though, is that USB ports seem to not be sourcing more than 100mA of current. I noticed that I can change the definition for maximum power in the V-USB configuration file (USB_CFG_MAX_BUS_POWER), but does this require a hardware change be made as well in order to implement it?

Basically, using either software or hardware, how do I get a USB port to output more than 100mA current?

Thanks in advance!