upas cron: clean up after greylist
 [rsc] --rw-rw-r-- M 628694 glenda sys 222 Apr 10 11:41 cron/upas/cron
	/n/sourcesdump/2006/0410/plan9/cron/upas/cron:2,5 - 
	/n/sourcesdump/2006/0411/plan9/cron/upas/cron:2,5
	  0,10,20,30,40,50 * * * *	mailserver		/bin/upas/runq -a /mail/queue /mail/lib/remotemail
	  
	  # clean up after grey list
	- 47 4 * * *	mailserver	cd /mail/grey && rm -f [0-9]*.[0-9]*.[0-9]*.[0-9]*
	+ 47 4 * * *	mailserver	rm -rf /mail/grey/tmp/*/*