diff --git a/htdocs/core/class/commonobject.class.php b/htdocs/core/class/commonobject.class.php
index b5043bf06d1..aa3fb034e32 100644
--- a/htdocs/core/class/commonobject.class.php
+++ b/htdocs/core/class/commonobject.class.php
@@ -3812,7 +3812,7 @@ abstract class CommonObject
 		$this->tpl['price'] = price($line->subprice);
 		$this->tpl['multicurrency_price'] = price($line->multicurrency_subprice);
 		$this->tpl['qty'] = (($line->info_bits & 2) != 2) ? $line->qty : ' ';
-		if($conf->global->PRODUCT_USE_UNITS) $this->tpl['unit'] = $line->getLabelOfUnit('long');
+		if ($conf->global->PRODUCT_USE_UNITS) $this->tpl['unit'] = $langs->transnoentities($line->getLabelOfUnit('long'));
 		$this->tpl['remise_percent'] = (($line->info_bits & 2) != 2) ? vatrate($line->remise_percent, true) : ' ';
 
 		// Is the line strike or not
diff --git a/htdocs/core/class/commonobjectline.class.php b/htdocs/core/class/commonobjectline.class.php
index 84c49f6392d..bed227eb408 100644
--- a/htdocs/core/class/commonobjectline.class.php
+++ b/htdocs/core/class/commonobjectline.class.php
@@ -51,8 +51,9 @@ abstract class CommonObjectLine extends CommonObject
 
 
     /**
-     *	Returns the text label from units dictionary
-     *
+     *	Returns the translation key from units dictionary.
+     *  A langs->trans() must be called on result to get translated value.
+     *  
      * 	@param	string $type Label type (long or short)
      *	@return	string|int <0 if ko, label if ok
      */