diff --git a/app/code/community/Bitpay/Core/Block/Iframe.php b/app/code/community/Bitpay/Core/Block/Iframe.php
index 4d14734..2504f59 100644
--- a/app/code/community/Bitpay/Core/Block/Iframe.php
+++ b/app/code/community/Bitpay/Core/Block/Iframe.php
@@ -23,7 +23,7 @@ class Bitpay_Core_Block_Iframe extends Mage_Checkout_Block_Onepage_Payment
      */
     public function getIframeUrl()
     {
-        if (Mage::getModel('bitpay/ipn')->getQuotePaid($this->getQuote()->getId())) {
+        if (\Mage::getModel('bitpay/ipn')->getQuotePaid($this->getQuote()->getId())) {
             return 'paid'; // quote's already paid, so don't show the iframe
         }
 
@@ -31,7 +31,7 @@ class Bitpay_Core_Block_Iframe extends Mage_Checkout_Block_Onepage_Payment
         $method  = $this->getQuote()->getPayment()->getMethodInstance();
 
         if (false === isset($method) || true === empty($method)) {
-            Mage::helper('bitpay')->debugData('[ERROR] In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not obtain an instance of the payment method.');
+            \Mage::helper('bitpay')->debugData('[ERROR] In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not obtain an instance of the payment method.');
             throw new Exception('In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not obtain an instance of the payment method.');
         }
 
@@ -39,18 +39,18 @@ class Bitpay_Core_Block_Iframe extends Mage_Checkout_Block_Onepage_Payment
             array(
                 'currency'          => $this->getQuote()->getQuoteCurrencyCode(),
                 'fullNotifications' => 'true',
-                'notificationURL'   => Mage::getUrl('bitpay/ipn'),
-                'redirectURL'       => Mage::getUrl('checkout/onepage/success'),
-                'transactionSpeed'  => Mage::getStoreConfig('payment/bitpay/speed'),
+                'notificationURL'   => \Mage::getUrl('bitpay/ipn'),
+                'redirectURL'       => \Mage::getUrl('checkout/onepage/success'),
+                'transactionSpeed'  => \Mage::getStoreConfig('payment/bitpay/speed'),
             ),
             $method->extractAddress($this->getQuote()->getShippingAddress())
         );
 
         if (false === isset($options) || true === empty($options)) {
-            Mage::helper('bitpay')->debugData('[ERROR] In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not merge the options array.');
+            \Mage::helper('bitpay')->debugData('[ERROR] In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not merge the options array.');
             throw new Exception('In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not merge the options array.');
         } else {
-            Mage::helper('bitpay')->debugData($options);
+            \Mage::helper('bitpay')->debugData($options);
         }
 
         // Mage doesn't round the total until saving and it can have more precision
@@ -59,7 +59,7 @@ class Bitpay_Core_Block_Iframe extends Mage_Checkout_Block_Onepage_Payment
         $price = round($this->getQuote()->getGrandTotal(), 4);
 
         if (false === isset($price) || true === empty($price)) {
-            Mage::helper('bitpay')->debugData('[ERROR] In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not get the new rounded price.');
+            \Mage::helper('bitpay')->debugData('[ERROR] In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not get the new rounded price.');
             throw new Exception('In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not get the new rounded price.');
         }
 
@@ -67,18 +67,18 @@ class Bitpay_Core_Block_Iframe extends Mage_Checkout_Block_Onepage_Payment
         $hash = $method->getQuoteHash($this->getQuote()->getId());
 
         if (false === isset($hash) || true === empty($hash)) {
-            Mage::helper('bitpay')->debugData('[ERROR] In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not get the quote hash.');
+            \Mage::helper('bitpay')->debugData('[ERROR] In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not get the quote hash.');
             throw new Exception('In Bitpay_Core_Block_Iframe::getIframeUrl(): Could not merge the quote hash.');
         }
 
-        Mage::helper('bitpay')->registerAutoloader();
+        \Mage::helper('bitpay')->registerAutoloader();
 
         //$invoice = bpCreateInvoice($quoteId, $price, array('quoteId' => $quoteId, 'quoteHash' => $hash), $options);
         $invoice = array('url' => 'https://test.bitpay.com/invoice?id=5NxFkXcJbCSivtQRJa4kHP');
 
         if (array_key_exists('error', $invoice)) {
-            Mage::helper('bitpay')->debugData(array('Error creating bitpay invoice', $invoice['error'],));
-            Mage::throwException("Error creating BitPay invoice. Please try again or use another payment option.");
+            \Mage::helper('bitpay')->debugData(array('Error creating bitpay invoice', $invoice['error'],));
+            \Mage::throwException("Error creating BitPay invoice. Please try again or use another payment option.");
 
             return false;
         }