Index: openacs-4/packages/xotcl-core/tcl/01-debug-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-core/tcl/01-debug-procs.tcl,v
diff -u -r1.78.2.17 -r1.78.2.18
--- openacs-4/packages/xotcl-core/tcl/01-debug-procs.tcl	30 Sep 2016 18:00:57 -0000	1.78.2.17
+++ openacs-4/packages/xotcl-core/tcl/01-debug-procs.tcl	1 Oct 2016 12:17:00 -0000	1.78.2.18
@@ -614,7 +614,10 @@
     @param value      the new value
   } {
     set package_key [apm_package_key_from_id $package_id]
-    if {$package_key eq "xotcl-core" && $parameter eq "NslogRedirector"} {
+    if {$package_key eq "xotcl-core"
+        && $parameter eq "NslogRedirector"
+        && [info commands ::xo::ns_log_redirector_manager] ne ""
+      } {
       ::xo::ns_log_redirector_manager set_level $value
       #
       # Update the blueprint to reflect the parameter change