I figured out my problem with building the ltmodem drivers with kernel 2.4.16 It turned out to be some strange problem with the kernel headers. I installed the headers from the kernel-headers-2.4.16 Debian package. This caused the ltmodem build script to not owrk because detecting an SMP configuration. What I end up doing was igonore the headers in the header module and use those in the kernel-source-2.4.16 package instead, by making a symbolic link. With this the build scripts worked just fine and now my LT modem is working!
Thanks, -- Ignasi.