Index: bp-activity/bp-activity-classes.php
===================================================================
--- bp-activity/bp-activity-classes.php	(revision 2470)
+++ bp-activity/bp-activity-classes.php	(working copy)
@@ -62,7 +62,8 @@
 		if ( !$wpdb->query( $q ) )
 			return false;
 
-		$this->id = $wpdb->insert_id;
+		if ( !$this->id )
+			$this->id = $wpdb->insert_id;
 
 		do_action( 'bp_activity_after_save', $this );
 		return true;