diff --git a/collects/help/help.ss b/collects/help/help.ss
index 98415854..a7563c6c 100644
--- a/collects/help/help.ss
+++ b/collects/help/help.ss
@@ -3,18 +3,38 @@
   (define install-cm? (getenv cm-env-var))
   (define cm-trace? (and install-cm? (equal? (getenv cm-env-var) "trace")))
   
-  (when install-cm?
-    (printf "~a: installing compilation manager\n" cm-env-var)
-    (let-values ([(make-compilation-manager-load/use-compiled-handler
-                   manager-trace-handler)
-                  (parameterize ([current-namespace (make-namespace)])
-                    (values
-                     (dynamic-require '(lib "cm.ss") 'make-compilation-manager-load/use-compiled-handler)
-                     (dynamic-require '(lib "cm.ss") 'manager-trace-handler)))])
-      (current-load/use-compiled (make-compilation-manager-load/use-compiled-handler))
-      (when cm-trace?
-        (manager-trace-handler
-         (lambda (x) (display x) (newline))))))
+  (define et-env-var "PLTHDDEBUG")
+  (define errortrace? (getenv et-env-var))
+  
+  (cond
+    [errortrace?
+     (printf "~a: installing errortrace & compilation manager\n" et-env-var)
+     (use-compiled-file-paths (list (build-path "compiled" "errortrace")))
+     (error-display-handler (dynamic-require '(lib "errortrace-lib.ss" "errortrace")
+                                             'errortrace-error-display-handler))
+     (let-values ([(current-managed-zo-compile
+                    make-compilation-manager-load/use-compiled-handler
+                    manager-trace-handler)
+                   (parameterize ([current-namespace (make-namespace)])
+                     (values
+                      (dynamic-require '(lib "cm.ss") 'current-managed-zo-compile)
+                      (dynamic-require '(lib "cm.ss") 'make-compilation-manager-load/use-compiled-handler)
+                      (dynamic-require '(lib "cm.ss") 'manager-trace-handler)))])
+       (current-managed-zo-compile
+        (dynamic-require '(lib "zo-compile.ss" "errortrace") 'zo-compile))
+       (current-load/use-compiled (make-compilation-manager-load/use-compiled-handler)))]
+    [install-cm?
+     (printf "~a: installing compilation manager\n" cm-env-var)
+     (let-values ([(make-compilation-manager-load/use-compiled-handler
+                    manager-trace-handler)
+                   (parameterize ([current-namespace (make-namespace)])
+                     (values
+                      (dynamic-require '(lib "cm.ss") 'make-compilation-manager-load/use-compiled-handler)
+                      (dynamic-require '(lib "cm.ss") 'manager-trace-handler)))])
+       (current-load/use-compiled (make-compilation-manager-load/use-compiled-handler))
+       (when cm-trace?
+         (manager-trace-handler
+          (lambda (x) (display x) (newline)))))])
   
   ;; start help desk for real
   (dynamic-require '(lib "help-app-main.ss" "help" "private") #f))
\ No newline at end of file