diff -dur cacti-plugin-thold-0.4.9.orig/thold/thold_functions.php cacti-plugin-thold-0.4.9/thold/thold_functions.php
--- cacti-plugin-thold-0.4.9.orig/thold/thold_functions.php	2012-12-11 17:47:07.000000000 +0100
+++ cacti-plugin-thold-0.4.9/thold/thold_functions.php	2012-12-11 17:48:34.789180077 +0100
@@ -1587,7 +1587,7 @@
 			thold_debug('Threshold Baseline check breached');
 
 			/* re-alert? */
-			$ra = ($item['bl_fail_count'] > $bl_fail_trigger && ($item['bl_fail_count'] % ($item['repeat_alert'] == '' ? $realert : $item['repeat_alert'])) == 0);
+			$ra = ($item['bl_fail_count'] > $bl_fail_trigger && ($item['bl_fail_count'] % ($item['repeat_alert'] == 0 ? $realert : $item['repeat_alert'])) == 0);
 
 			$notify = ($item['bl_fail_count'] == $bl_fail_trigger || $ra);