Erro no Magento com PagSeguro

Usando o Magento com PagSeguro ocorreu um erro ao fechar a venda, logo após seguir para o próximo passo (2). O report do erro é o seguinte:

a:5:{i:0;s:118:"Notice: Undefined offset: 2 in

/home/sfa/www/e-com-m/app/code/community/PagSeguro/Model/Carrier/frete.php on line 96";i:1;s:2385:"#0

/home/sfa/www/e-com-m/app/code/community/PagSeguro/Model/Carrier/frete.php(96):

mageCoreErrorHandler(8, 'Undefined offse...', '/home/sfa/www/e...', 96, Array)

#1

/home/sfa/www/e-com-m/app/code/community/PagSeguro/Model/Carrier/ShippingMethod.php(80):

PgsFrete->gerar('-', 3, NULL, '91230250')

#2

/home/sfa/www/e-com-m/app/code/community/PagSeguro/Model/Carrier/ShippingMethod.php(29):

PagSeguro_Model_Carrier_ShippingMethod->pegaFrete(3, '91230250', NULL)

#3

/home/sfa/www/e-com-m/app/code/core/Mage/Shipping/Model/Shipping.php(141):

PagSeguro_Model_Carrier_ShippingMethod->collectRates(Object(Mage_Shipping_Model_Rate_Request))

#4

/home/sfa/www/e-com-m/app/code/core/Mage/Shipping/Model/Shipping.php(107): Mage_Shipping_Model_Shipping->collectCarrierRates('pagseguro', Object(Mage_Shipping_Model_Rate_Request))

#5

/home/sfa/www/e-com-m/app/code/core/Mage/Sales/Model/Quote/Address.php(644): Mage_Shipping_Model_Shipping->collectRates(Object(Mage_Shipping_Model_Rate_Request))

#6 /home/sfa/www/e-com-m/app/code/core/Mage/Sales/Model/Quote/Address/Total/Shipping.php(155): Mage_Sales_Model_Quote_Address->collectShippingRates()

#7 /home/sfa/www/e-com-m/app/code/core/Mage/Sales/Model/Quote/Address.php(708): Mage_Sales_Model_Quote_Address_Total_Shipping->collect(Object(Mage_Sales_Model_Quote_Address))

#8 /home/sfa/www/e-com-m/app/code/core/Mage/Sales/Model/Quote.php(908): Mage_Sales_Model_Quote_Address->collectTotals()

#9 /home/sfa/www/e-com-m/app/code/core/Mage/Checkout/Model/Cart.php(357): Mage_Sales_Model_Quote->collectTotals()

#10 /home/sfa/www/e-com-m/app/code/core/Mage/Checkout/controllers/CartController.php(117): Mage_Checkout_Model_Cart->save()

#11 /home/sfa/www/e-com-m/app/code/core/Mage/Core/Controller/Varien/Action.php(418): Mage_Checkout_CartController->indexAction()

#12 /home/sfa/www/e-com-m/app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(254): Mage_Core_Controller_Varien_Action->dispatch('index')

#13 /home/sfa/www/e-com-m/app/code/core/Mage/Core/Controller/Varien/Front.php(177): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http))

#14 /home/sfa/www/e-com-m/app/code/core/Mage/Core/Model/App.php(304): Mage_Core_Controller_Varien_Front->dispatch()

#15 /home/sfa/www/e-com-m/app/Mage.php(596): Mage_Core_Model_App->run(Array)

#16 /home/sfa/www/e-com-m/index.php(78): Mage::run('', 'store')

#17 {main}";s:3:"url";s:33:"/e-com-m/index.php/checkout/cart/";s:11:"script_name";s:18:"/e-com-m/index.php";s:4:"skin";s:7:"default";}

Para corrigir eu tive que desabilitar a opção de Frete por PagSeguro.

Tentei inicialmente desativar o PagSeguro no modulo System -> Configuration -> Payment Method, mas isso não foi suficiente. Desativei então frete em Shipping Methods e então resolveu.

Se alguém souber a soluçãopara o problema sem desativar o pagSeguro favor postar sua resposta.