Only in maildrop-1.8.0/maildir: #maildirquota.c#
diff -ur maildrop-1.8.0.orig/maildir/maildirquota.c maildrop-1.8.0/maildir/maildirquota.c
--- maildrop-1.8.0.orig/maildir/maildirquota.c	2004-06-27 00:20:13.000000000 +0900
+++ maildrop-1.8.0/maildir/maildirquota.c	2005-04-14 10:00:05.348145623 +0900
@@ -294,9 +294,15 @@
 			q->nmessages=i;
 			break;
 		default:
+			/* default is MDQUOTA_SIZE */
+			q->nbytes=i;
+			break;
+
+			/*
 			fprintf(stderr, "WARN: quota string '%s' not parseable\n",
 				quota_start);
 			break;
+			*/
 		}
 	}
 }