--- a/src/procmail.c
+++ b/src/procmail.c
@@ -652,7 +652,7 @@
 	      nrcond= -1;
 	   if(tolock)		 /* clear temporary buffer for lockfile name */
 	      free(tolock);
-	   bbzero(flags,maxindex(flags));		  /* clear the flags */
+	   bbzero(flags,sizeof(flags));		  /* clear the flags */
 	   for(tolock=0,locknext=0;;)
 	    { chp=skpspace(chp);
 	      switch(i= *chp++)
