If you choose to follow these directions, do so at your own risk. You could fry your Touchstone dock, usb adapter or overheat and start a fire if you're not careful. This is the definition of a dirty hack, but does answer some questions about the charging.

The Palm Touchstone dock seems to look for chargers that support the new USB Fast Charging standard. This standard allows for simple, cheaply produced chargers to charge devices more quickly. (Credit: Wikipedia article on Universal Serial Bus)

As a way of keeping things cheap, these Fast Chargers indicate their ability to provide higher than normal current to the device by shorting the D+ and D- pins on the USB cable together. This way the charger can signal to the device that it can provide the higher current without any special electronics to communicate with the device, which would raise the manufacturing cost. This is the center two pins in a standard USB A cable.

To test this, I verified this behavior with a multimeter. Sure enough, on the Palm chargers, the two middle pins are tied together. On the USB chargers that don't work with the Touchstone, there is no continuity between the two middle pins.

As an experiment, I decided to sacrifice a cheap Micro USB Cable (thanks Monoprice!) to see if one could make a cable that works with regular USB chargers. I cut the insulation off around the cable near the A connector side, clipped the White and Green wires and tied them together (The side connected to the Micro USB, not the charger side). I then plugged my modded cable into the adapter from my old iPhone which did not work before, hooked it up to the Touchstone, set the Pre on top and it lit right up and began charging. Obviously if you were to use this as a permanent solution you should soldier the wires together and make sure everything is properly insulated with tape and heat shrink.

I probably wouldn't have been willing to try a hack like this if it required plugging this hacked up cable into the actual phone, but I was willing to try it with the Touchstone dock in the middle so I could satisfy my own curiosity.

If you try this (and I suggest you don't), remember that your USB cable will never again be good for data transfer again. Also, if you use a USB adapter that is not capable of supplying the full 1 amp of 5V DC (like Palm's does), you could burn up your adapter and/or start a fire.

I've taken some pictures, but I'm assuming since this is my first post I'm not allowed to post them. I'll try and get them up somewhere else tonight in case anyone's curious.

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