I've reversed engineer the CableServer communication with Impact and written from scratch a brand new CableServer. Currently only Parallel III cable is implemented, but new cables can be added very easily. I will post the project on sourceforge.net next week.
Antti wasn't really helpful to come up with a name for the project, so it will be called "cblsrv" :)
I've uninstalled windriver from Win32 and Impact seems to work without it if only "cblsrv" is used. I guess the same is true for Linux as well.
Zoltan