diff --git a/collects/readline/rep.ss b/collects/readline/rep.ss
index 2bb64f2026..fc9de67436 100644
--- a/collects/readline/rep.ss
+++ b/collects/readline/rep.ss
@@ -10,4 +10,10 @@
     (error 'readline-input
            "invoke this library when the current-input-port is stdin"))
 
-  (current-prompt-read read-cmdline-syntax))
+  (current-prompt-read 
+   (let ([orig-read (current-prompt-read)]
+         [orig-input (current-input-port)])
+     (lambda ()
+       (if (eq? (current-input-port) orig-input)
+           (read-cmdline-syntax)
+	   (orig-read))))))