diff --git a/app/code/core/Mage/Sales/Model/Order.php b/app/code/core/Mage/Sales/Model/Order.php
index b561fa127c8..d9dfe093310 100644
--- a/app/code/core/Mage/Sales/Model/Order.php
+++ b/app/code/core/Mage/Sales/Model/Order.php
@@ -2012,13 +2012,14 @@ public function formatPricePrecision($price, $precision, $addBrackets = false)
     }
 
     /**
-     * Retrieve text formatted price value including order rate
+     * Retrieve currency formatted string.
      *
-     * @param   float $price
-     * @return  string
+     * @param float|string $price Numeric value or field name, e.g. "grand_total".
+     * @return string
      */
     public function formatPriceTxt($price)
     {
+        $price = (float) (is_numeric($price) ? $price : $this->_getData($price));
         return $this->getOrderCurrency()->formatTxt($price);
     }