diff --git a/htdocs/projet/class/project.class.php b/htdocs/projet/class/project.class.php
index 90057832c23..7f0da4a6c98 100644
--- a/htdocs/projet/class/project.class.php
+++ b/htdocs/projet/class/project.class.php
@@ -792,7 +792,7 @@ class Project extends CommonObject
 			}
 		}
 		if (count($sqlwhere) > 0) {
-			$sql .= ' AND ('.implode(' '.$filtermode.' ', $sqlwhere).')';
+			$sql .= ' AND ('.implode("'.$filtermode.'", $sqlwhere).')';
 		}
 
 		if (!empty($sortfield)) {