You might want to investigate using udev
to customize the device name. Here is a decent rule writing guide
to help you get started, but the basic idea is that hotplug can recognize the USB ID number of your palm device and then create a device in /dev that you named in udev. For example, if you always want your palm to be /dev/palm rather than /dev/ttyUSB?, you write a udev rule so that when hotplug sees that devices ID number, it creates /dev/palm. Basically, udev allows you to customize the /dev naming conventions so you don't have to go hunting for your devices. I've used it quite successfully with a digital camera and a USB memory stick.