MINI PRO. SPIEN fuse problem

Hi I had a MINI PRO connected to Studio 4 via the ISP connection. downloaded some software and tried to run the dubugger. The debugger had problems an changed to debugWIRE mode. That didnt work either. Upon inspection using the ISP connection (and dragon) the SPIEN fuse had become unset. Is there ant way to reset this fuse. The chip is a atmega328P Hugh