kgohostvieew, gv does not work!!

hi People, I have no idea what I have done but neither kghostview nor gv is working..When I click on a ps file kgohostview tells me "Could not start Ghostscript. This is most likely caused by an incorrectly specified interpreter" When I open the configure panel, and click on defaults nothing is being loaded. the interpreter is "gs" when i enter this commadn on the command line it says "command not found" same thing is happening with gv as well.... can somebody help? i had done an update of KDE but now I installed back my distributions KDE (SuSE Pro 8) it didnt solve the problem.... thanks baris