If you've compiled ppdev using the tc .config file and changing just the line to produce ppdev, then "make modules_install" will place ppdev.ko somewhere under /lib.
Once you've found where ppdev is, you can make an extension out of it by doing something like:$ sudo tar -czvf ppdev.tcem --numeric-owner /path-to-file/ppdev.ko
You can then reboot with the standard tc kernel, load the new extension and be good to go.