fixed for issue #1 Headers a case sensitive

lib/active_merchant/billing/gateways/paypal_adaptive_payments.rb

@@ -1,6 +1,8 @@
 dir = File.dirname(__FILE__)
 require dir + '/paypal_adaptive_payments/exceptions.rb'
 require dir + '/paypal_adaptive_payments/adaptive_payment_response.rb'
+require dir + '/paypal_adaptive_payments/ext.rb'
+require dir + '/paypal_adaptive_payments/version.rb'
 
 module ActiveMerchant #:nodoc:
   module Billing #:nodoc:

lib/active_merchant/billing/gateways/paypal_adaptive_payments/ext.rb

@@ -0,0 +1,14 @@
+module Net
+  module HTTPHeader
+
+    #fix for case sensitive headers in paypal (issue #1)
+    def []= key, val
+      unless val
+        @header.delete key
+        return val
+      end
+      @header[key] = [val]
+    end
+
+  end
+end

lib/active_merchant/billing/gateways/paypal_adaptive_payments/version.rb

@@ -0,0 +1,10 @@
+module ActiveMerchant
+  module Billing
+    class PaypalAdaptivePaymentGateway < Gateway # :nodoc
+      def version
+        {:major => 0, :minor => 1, :patchlevel => 3}
+      end
+    end
+  end
+
+end