RedHat 6.0 is missing the teles_cs.o module that is required to be used when you use PCMCIA Teles ISDN-card.
This may or may not happen. We use the lastest pcmcia sources with each release as distributed from David Hinds ftp site. You card shows up in the contributed drivers list which has the following statement. The following cards have contributed drivers which are distributed as separate packages. The drivers are not included in the base PCMCIA package for maintenance reasons: they are for less common cards and I cannot test them. You can obtain the source for your particular card from ftp://csb.stanford.edu/pub/pcmcia/contrib/ and apply them to the pcmcia source tree under /usr/src/linux and the recompile and install the proper modules.