How to configure RCS not to do a diff -a on Sun Solaris??

[Karen]

Any help or suggestions much appreciated.

I was using rcs on a linux box no prob. We migrated to sun and our
sysadmin installed rcs.
However, on doing a ci rcs tries to do a diff with the -a option which
does not exist on this platform.
is there a way I can configure this and/or other rcs options? Can't find
good documentation on this.

Thanks!
Karen