title: Ultracart Shipping Method Error
body: <p>I am using ultracart api for my cart system and i want to complete a free order for testing purpose if anyone could help regarding Ultracart's this error
  "Unknown shipping method specified".
  I am using the shipping method USPS: 2-Day 
  <strong>Following is the code where shipping method is specified</strong></p>
  
  <h2>Code</h2>
  
  <pre><code> function checkout() {
    var cart = {
      'merchantId': 'DEMO',
      'cartId': '', // will be populated by call
  
      "customField1": 'blah blah blah',
      "customField2": 'perhaps an affiliate id here?',
      "coupons": [
        {couponCode: '10OFF'}
      ], // here is a coupon for $10 off the order
      "advertisingSource": "Radio",
      "screenBrandingThemeCode": "CSTM", // The demo account has a second them set up using the code CSTM
      "shippingMethod": "USPS: 2-Day",
      "shipToFirstName": "Testy",
      "shipToLastName": "Testerson",
      "shipToTitle": "Sir",
      "shipToCompany": "Ultra Trains",
      "shipToAddress1": "55 Main Street",
      "shipToAddress2": "Suite 101",
      "shipToCity": "Duluth",
      "shipToState": "GA",
      "shipToPostalCode": "30097",
      "shipToCountry": "United States",
      "shipToPhone": "555-555-1212",
      "shipToEveningPhone": "5555553434", // notice the different format?
      "billToDayPhone": "555-555-1212",
      "billToEveningPhone": "5555551212",
      "billToFirstName": "Smith",
      "billToLastName": "Joe",
      "billToTitle": "Chief",
      "billToCompany": "Widgets, INC",
      "billToAddress1": "2000 Montana Dr",
      "billToAddress2": "",
      "billToCity": "Duluth",
      "billToState": "GA",
      "billToPostalCode": "30097",
      "billToCountry": "United States",
      "email": "test@test.com",
      "emailConfirm": "test@test.com",
      "paymentMethod": "Credit Card",
      "creditCardType": "VISA",
      "creditCardNumber": "4444333322221111",
      "creditCardExpirationMonth": 12,
      "creditCardExpirationYear": 2028,
      "creditCardVerificationNumber": "123",
      'items': [
        {'itemId': 'PDF', 'quantity': 1},
        {'itemId': 'Baseball', 'quantity': 2},
        {'itemId': 'BONE', 'quantity': 5}
      ]
    };
  </code></pre>