Index: openacs-4/packages/forums/www/message-post.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/forums/www/message-post.tcl,v
diff -u -N -r1.46 -r1.47
--- openacs-4/packages/forums/www/message-post.tcl	11 Oct 2017 16:07:55 -0000	1.46
+++ openacs-4/packages/forums/www/message-post.tcl	13 Oct 2017 09:39:12 -0000	1.47
@@ -12,16 +12,16 @@
 } -validate {
     forum_id_or_parent_id {
         if {$forum_id eq "" && $parent_id eq ""} {
-          ad_complain [_ forums.lt_You_either_have_to]
+            ad_complain [_ forums.lt_You_either_have_to]
         }
-        if {$forum_id ne "" && ![string is integer $forum_id]} {
-            ad_complain [_ acs-templating.Invalid_integer]
-        }
         if {$forum_id ne "" && ![forum::valid_forum_id_p -forum_id $forum_id]} {
             ad_complain [_ acs-templating.Invalid_integer]
         }
-        if {$parent_id ne "" && ![string is integer $parent_id]} {
-            ad_complain [_ acs-templating.Invalid_integer]
+        if {$parent_id ne ""} {
+            forum::message::get -message_id $parent_id -array parent_message
+            if {![info exists parent_message]} {
+                ad_complain [_ acs-templating.Invalid_integer]
+            }
         }
     }
 }
@@ -56,7 +56,6 @@
     }
 } else {
     # get the parent message information
-    forum::message::get -message_id $parent_id -array parent_message
     set parent_message(tree_level) 0
 
     # see if they're allowed to add to this thread