diff --git a/htdocs/projet/class/project.class.php b/htdocs/projet/class/project.class.php
index f58886c9a3b..4fff4297854 100644
--- a/htdocs/projet/class/project.class.php
+++ b/htdocs/projet/class/project.class.php
@@ -2135,50 +2135,8 @@ class Project extends CommonObject
 	 */
 	public function setCategories($categories)
 	{
-		$type_categ = Categorie::TYPE_PROJECT;
-
-		// Handle single category
-		if (!is_array($categories)) {
-			$categories = array($categories);
-		}
-
-		// Get current categories
 		require_once DOL_DOCUMENT_ROOT.'/categories/class/categorie.class.php';
-		$c = new Categorie($this->db);
-		$existing = $c->containing($this->id, $type_categ, 'id');
-
-		// Diff
-		if (is_array($existing)) {
-			$to_del = array_diff($existing, $categories);
-			$to_add = array_diff($categories, $existing);
-		} else {
-			$to_del = array(); // Nothing to delete
-			$to_add = $categories;
-		}
-
-		// Process
-		foreach ($to_del as $del) {
-			if ($c->fetch($del) > 0) {
-				$result = $c->del_type($this, $type_categ);
-				if ($result < 0) {
-					$this->errors = $c->errors;
-					$this->error = $c->error;
-					return -1;
-				}
-			}
-		}
-		foreach ($to_add as $add) {
-			if ($c->fetch($add) > 0) {
-				$result = $c->add_type($this, $type_categ);
-				if ($result < 0) {
-					$this->errors = $c->errors;
-					$this->error = $c->error;
-					return -1;
-				}
-			}
-		}
-
-		return 1;
+		return parent::setCategoriesCommon($categories, Categorie::TYPE_PROJECT);
 	}