diff --git a/ice-9/ChangeLog b/ice-9/ChangeLog
index e96d7d306..a399dc69b 100644
--- a/ice-9/ChangeLog
+++ b/ice-9/ChangeLog
@@ -1,3 +1,8 @@
+2008-04-14  Neil Jerram  <neil@ossau.uklinux.net>
+
+	* gds-client.scm (gds-debug-trap): Ensure that frame index passed
+	to Emacs is always positive.
+
 2008-03-19  Neil Jerram  <neil@ossau.uklinux.net>
 
 	* debugging/ice-9-debugger-extensions.scm (command-loop): Use
diff --git a/ice-9/gds-client.scm b/ice-9/gds-client.scm
index 7e6e524e5..903e803e5 100755
--- a/ice-9/gds-client.scm
+++ b/ice-9/gds-client.scm
@@ -73,7 +73,9 @@
 					     (slot-ref (car fired-traps) 'depth)))))
                  ;; Write current stack to the frontend.
                  (write-form (list 'stack
-				   (or special-index 0)
+				   (if (and special-index (> special-index 0))
+				       special-index
+				       0)
                                    (stack->emacs-readable stack)
                                    (append (flags->emacs-readable flags)
                                            (slot-ref trap-context