diff --git a/sources/application/search/criterionconversion/criteriontosearchform.class.inc.php b/sources/application/search/criterionconversion/criteriontosearchform.class.inc.php
index a376eab97..0a0bc1bb7 100644
--- a/sources/application/search/criterionconversion/criteriontosearchform.class.inc.php
+++ b/sources/application/search/criterionconversion/criteriontosearchform.class.inc.php
@@ -60,6 +60,7 @@ class CriterionToSearchForm extends CriterionConversionAbstract
 			AttributeDefinition::SEARCH_WIDGET_TYPE_DATE => 'DateToSearchForm',
 			AttributeDefinition::SEARCH_WIDGET_TYPE_DATE_TIME => 'DateTimeToSearchForm',
 			AttributeDefinition::SEARCH_WIDGET_TYPE_NUMERIC => 'NumericToSearchForm',
+			AttributeDefinition::SEARCH_WIDGET_TYPE_EXTERNAL_KEY => 'ExternalKeyToSearchForm',
 		);
 
 		foreach($aAndCriterionRaw as $aCriteria)
@@ -387,4 +388,14 @@ class CriterionToSearchForm extends CriterionConversionAbstract
 	}
 
 
+	protected static function ExternalKeyToSearchForm($aCriteria, $aFields)
+	{
+		if ($aCriteria['operator'] == '=')
+		{
+			$aCriteria['operator'] = CriterionConversionAbstract::OP_IN;
+		}
+
+		return $aCriteria;
+	}
+
 }
\ No newline at end of file