diff --git a/collects/repos-time-stamp/stamp.ss b/collects/repos-time-stamp/stamp.ss
index 2f7a99d275..8aab08c2e7 100644
--- a/collects/repos-time-stamp/stamp.ss
+++ b/collects/repos-time-stamp/stamp.ss
@@ -1 +1,10 @@
-#lang scheme/base (provide stamp) (define stamp "2mar2009")
+#lang scheme/base
+(provide stamp) 
+(define stamp
+  (string-append "2mar2009 "
+		 (let ([s "$URL$"])
+		   (substring 
+		    s 0
+		    (- (string-length s)
+		       (string-length
+			"collects/repos-time-stamp/stamp.ss"))))))