SOLVED.
Many thanks James for taking the time to compile the 2.6.7 kernel. I compiled it in the end and the slmodem-2.9.9 driver worked okay. It was a bit fiddly getting it going with Gnome, but now my modem works fine.
Now I just need to get some scripts together so that it starts up easily every time I boot, which shouldn't be much of a problem.
Art.
Original problem:
Building the winmodem slmodem-2.9.9 driver in kernel 2.6.6-x and kernel 2.6.5-x
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