Index: openacs-4/packages/chat/tcl/apm-callback-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/chat/tcl/Attic/apm-callback-procs.tcl,v
diff -u -N -r1.1.2.6 -r1.1.2.7
--- openacs-4/packages/chat/tcl/apm-callback-procs.tcl	9 Feb 2020 15:30:16 -0000	1.1.2.6
+++ openacs-4/packages/chat/tcl/apm-callback-procs.tcl	19 Oct 2021 08:32:06 -0000	1.1.2.7
@@ -30,7 +30,7 @@
                     select parameter_id, parameter_name
                       from apm_parameters
                     where package_key = 'chat'
-                      and parameter_name in ('[join $parameter_names ',']')
+                    and parameter_name in ([ns_dbquotelist $parameter_names])
                 }] {
                     apm_parameter_unregister \
                         -package_key chat $parameter_id