Which version of the tools are you using (Help->About in the CIW, and "spectre -W" at the UNIX command line - subversion also shown at the top of the spectre log file)? If using IC614/IC615 and (say) MMSIM10.1, MMSIM11.1 or MMSIM12.1 I would recommend changing the output format to "psfxl" rather than sst2 (This is on the Outputs->Save All form).
However, I think the specific issue you're seeing is quite likely fixed if you're using a recent enough subversion of MMSIM10.1, MMSIM11.1 or MMSIM12.1
Regards,
Andrew.