diff --git a/htdocs/compta/facture.php b/htdocs/compta/facture.php
index adee547db8a..88212760c4d 100644
--- a/htdocs/compta/facture.php
+++ b/htdocs/compta/facture.php
@@ -988,8 +988,9 @@ if ($_POST['action'] == 'updateligne' && $user->rights->facture->creer && $_POST
 		$product->fetch($productid);
 		$type=$product->type;
 	}
-	if($product->price_min && ($_POST['productid']!='') && (price2num($_POST['price'])*(1-price2num($_POST['remise_percent'])/100) < price2num($product->price_min)))
+	if ($product->price_min && GETPOST('productid') && (price2num(GETPOST('subprice'))*(1-price2num(GETPOST('remise_percent'))/100) < price2num($product->price_min)))
 	{
+	    print "CantBeLessThanMinPrice ".GETPOST('subprice')." - ".GETPOST('remise_percent')." - ".$product->price_min;
 		$mesg = '<div class="error">'.$langs->trans("CantBeLessThanMinPrice",price2num($product->price_min,'MU').' '.$langs->trans("Currency".$conf->monnaie)).'</div>';
 		$result=-1;
 	}