Hi just came across this patch for pppoatm:
http://www.sfgoth.com/~mitch/linux/atm/pppoatm/ might solve problems patching and compiling that Guillame has been having? the page seems to be old (the kernel patch is no longer needed and is for 2.4.0test2!) interestingly though, it says you need the linux-atm userland environment installed - is this still necessary? Cheers cris.