Index: openacs-4/etc/install/tcl/dotlrn-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/etc/install/tcl/dotlrn-procs.tcl,v
diff -u -N -r1.11 -r1.12
--- openacs-4/etc/install/tcl/dotlrn-procs.tcl	5 Jan 2004 12:26:55 -0000	1.11
+++ openacs-4/etc/install/tcl/dotlrn-procs.tcl	10 Jan 2007 21:21:59 -0000	1.12
@@ -265,5 +265,5 @@
     ::twt::assert_equals \
             "Should be one less class to dergister from after deregistering" \
             $deregister_count_after \
-            [expr $deregister_count_before - 1]
+            [expr {$deregister_count_before - 1}]
 }