This issue is only relevant to very old versions of Zaptel: fixed in 1.2 .
I asked Digium sales support about compiling Zaptel on an AMD64 / x86_64 / SMP Opteron system prior to buying a card from them. Their response was:
“The only thing you’ll need to do with regards to compilation is to add: -mcmodel=kernel to the first KFLAGS definition in the Zaptel Makefile. You’ll also want to make sure that the TDM card isn’t sharing an interrupt with your USB controller. “
I’ve used this on builds from 1.0.4 to 1.0.9 with success.