Old versions of ORCA 8 clobber source code on compilation. This will never be fixed, but there is a local installation of ORCA 8_7_5 in /code/osgcode/cmslocal (instead of /code/osgcode/cmssoft) which doesn't clobber code on compilation. This software is no longer supported and you should really be using CMSSW for future work.
-- JamesLetts - 10 Jan 2007
-- FkW - 14 Jul 2006