diff --git a/collects/help/private/search.ss b/collects/help/private/search.ss
index e17cdf78..cdb78587 100644
--- a/collects/help/private/search.ss
+++ b/collects/help/private/search.ss
@@ -5,7 +5,8 @@
            "manuals.ss"
            (lib "list.ss")
            (lib "plt-match.ss")
-           (lib "contract.ss"))
+           (lib "contract.ss")
+	   (lib "dirs.ss" "setup"))
   
   (provide doc-collections-changed)
   (provide/contract
@@ -33,6 +34,7 @@
    
    (non-regexp (string? . -> . string?)))
 
+  (define doc-dirs (get-doc-search-dirs))
   
   ; These are set by reset-doc-lists:
   ; docs, doc-names and doc-kinds are parallel lists. doc-kinds
@@ -44,8 +46,12 @@
   ; doc-kinds : (list-of symbol)
   (define doc-kinds null)
   ; doc-collection-date : (union #f number 'none)
-  (define doc-collection-date #f)
+  (define doc-collection-dates (map (lambda (x) #f) doc-dirs))
   
+  (define (dir-date/none dir)
+    (with-handlers ([exn:fail:filesystem? (lambda (x) 'none)])
+      (file-or-directory-modify-seconds dir)))
+
   (define (reset-doc-lists)
   ; Locate standard HTML documentation
     (define-values (std-docs std-doc-names)
@@ -64,10 +70,7 @@
 			  txt-doc-names)))
     (set! doc-kinds (append (map (lambda (x) 'html) std-docs) (map (lambda (x) 'text) txt-docs)))
     
-    (with-handlers ([exn:fail:filesystem? (lambda (x) (set! doc-collection-date 'none))])
-		   (set! doc-collection-date 
-			 (file-or-directory-modify-seconds
-			  (collection-path "doc")))))
+    (set! doc-collection-dates (map dir-date/none doc-dirs)))
   
   (define MAX-HIT-COUNT 300)
   
@@ -284,7 +287,7 @@
        (string->list s)))))
       
   (define (doc-collections-changed)
-    (set! doc-collection-date #f)
+    (set! doc-collection-dates (map (lambda (x) #f) doc-dirs))
     (set! html-keywords (make-hash-table 'equal))
     (set! html-indices (make-hash-table 'equal))
     (set! text-keywords (make-hash-table 'equal))
@@ -325,11 +328,18 @@
                      add-doc-section add-kind-section add-choice)
     ; When new docs are installed, the directory's modification date changes:
     (set! max-reached #f)
-    (unless (eq? doc-collection-date 'none)
-      (when (or (not doc-collection-date)
-                (> (file-or-directory-modify-seconds (collection-path "doc"))
-                   doc-collection-date))
-        (reset-doc-lists)))
+
+    (when (ormap (lambda (date new-date)
+		   (cond
+		    [(not date) #t]
+		    [(equal? date new-date) #f]
+		    [(eq? date 'none) #t]
+		    [(eq? new-date 'none) #t]
+		    [else (new-date . > . date)]))
+		 doc-collection-dates
+		 (map dir-date/none doc-dirs))
+      (reset-doc-lists))
+
     (let ([hit-count 0])
       (let-values ([(string-finds finds) (build-string-finds/finds given-find regexp? exact?)]
                    [(filtered-docs filtered-doc-names filtered-doc-kinds)