Segmentation fault

I have a new Redhat 9 system that sometimes gives problems at shutdown time. If this happens it will not boot up again beyond the “Interactive mode Y/N” point. (nasty!) At shutdown I get TERM signal then /etc/rc.d/rc: line 68 18723 segmentation fault egrep -q “(killproc | action)” $i. Sometimes shutdown works fine.
I wonder if it is related to remote X logins or webmin? Any advice welcome – Sandy