When you move a forum message to another forum the cache of the target forum doesn't update, therefore you can't access the moved message neither in the source nor in the target forum
I solved this proved added next source in line 73 on www/moderate/move.tcl file:
<u>actual code</u>
#update initial forum: decrease thread_count, approved_thread_count and max_child_sortkey, update last_post
db_0or1row forums::move_message::select_data_forum_initial {}
db_dml forums::move_message::update_forum_initial {}
<u>Code added after these lines</u>
cache flush "messages,forum_id=$forum_id*"
<u>Patch</u>
Index: move.tcl
===================================================================
RCS file: /web/cvsrep/dotalf/packages/forums/www/moderate/move.tcl,v
retrieving revision 1.1.1.1
diff -r1.1.1.1 move.tcl
72a73,76
# DRB: Black magic cache flush call which will disappear when list builder is
# rewritten to paginate internally rather than use the template paginator.
cache flush "messages,forum_id=$forum_id*"
