CLIM-USER> (accept-from-string 'integer "12345" :start 1)
123
INTEGER
5
CLIM-USER>

Fix:

--- mcclim-cvs/presentation-defs.lisp	2008-05-27 06:15:36.000000000 -0700
+++ mcclim-local/presentation-defs.lisp	2009-01-20 14:02:55.000000000 -0800
@@ -982,7 +982,7 @@
                                        &allow-other-keys)
   (setf (stream-input-buffer stream)
         (replace (make-array (- end start) :fill-pointer (- end start))
-                 string :start1 start :end2 end)))
+                 string :start2 start :end2 end)))
 
 (defmethod stream-element-type ((stream string-input-editing-stream))
   'character)
