Index: openacs-4/packages/bulk-mail/tcl/bulk-mail-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/bulk-mail/tcl/bulk-mail-procs.tcl,v
diff -u -N -r1.18.2.4 -r1.18.2.5
--- openacs-4/packages/bulk-mail/tcl/bulk-mail-procs.tcl	10 Feb 2021 14:47:49 -0000	1.18.2.4
+++ openacs-4/packages/bulk-mail/tcl/bulk-mail-procs.tcl	10 Feb 2021 15:02:56 -0000	1.18.2.5
@@ -309,7 +309,7 @@
 
                 # both html and plain messages can now be sent the same way
                 acs_mail_lite::send \
-                    -to_addr $to_addr \
+                    -to_addr [list $to_addr] \
                     -from_addr $from_addr \
                     -subject $subject \
                     -body $message \