diff --git a/src/mred/wrap/mred.ss b/src/mred/wrap/mred.ss
index dccf8c27..2e541534 100644
--- a/src/mred/wrap/mred.ss
+++ b/src/mred/wrap/mred.ss
@@ -4686,26 +4686,27 @@
 				    (let ([l (with-handlers ([void (lambda (x) null)])
 					       (directory-list dir))]
 					  [dot? (send dot-check get-value)])
-				      (letrec ([sort (lambda (l)
-						       (if (or (null? l) (null? (cdr l)))
-							   l
-							   (let-values ([(l1 l2) (split l null null)])
-							     (merge (sort l1) (sort l2)))))]
-					       [split (lambda (l l1 l2)
-							(cond
-							 [(null? l) (values l1 l2)]
-							 [(null? (cdr l)) (values (cons (car l) l1) l2)]
-							 [else (split (cddr l) (cons (car l) l1) (cons (cadr l) l2))]))]
+				      (letrec ([split (lambda (n l)
+							(if (null? l)
+							    '(() . ())
+							    (if (< n 1)
+								(cons (list (car l)) (cdr l))
+								(let ([n (quotient n 2)])
+								  (let* ([r1 (split n l)]
+									 [r2 (split n (cdr r1))])
+								    (cons (merge (car r1) (car r2)) (cdr r2)))))))]
 					       [merge (lambda (l1 l2)
 							(cond
 							 [(null? l1) l2]
 							 [(null? l2) l1]
-							 [(string<? (car l1) (car l2)) (cons (car l1) (merge (cdr l1) l2))]
-							 [else (merge l2 l1)]))])
+							 [(string<? (car l1) (car l2)) 
+							  (cons (car l1) (merge (cdr l1) l2))]
+							 [else (cons (car l2) (merge (cdr l2) l1))]))]
+					       [sort (lambda (l) (car (split (length l) l)))])
 					(let-values ([(ds fs)
 						      (let loop ([l l][ds null][fs null])
 							(cond
-							 [(null? l) (values (cons ".." (sort (reverse! ds))) (sort (reverse! fs)))]
+							 [(null? l) (values (cons ".." (sort ds)) (sort fs))]
 							 [(and (not dot?) (char=? (string-ref (car l) 0) #\.)) (loop (cdr l) ds fs)]
 							 [(file-exists? (build-path dir (car l))) (loop (cdr l) ds (cons (car l) fs))]
 							 [else (loop (cdr l) (cons (car l) ds) fs)]))])