title: Tag appears more than once while using Quickfix market data incremental refresh
body: <p>I have implemented the fix client that request for market data. I have successfully logged on to the server but when the server sends us a MarketDataIncrementalRefresh message my application rejects with the message "Tag appears more than once" tag for which it is indicating is 55. Can you please help me in resolving it?
  The message it rejects is:
  8=FIX.4.2 9=196 35=X 34=14 49=Xenfin 56=newchange.api -price 52=20140528-08:54:32.144 262=156 268=2  279=1 269=0 278=B 55=EUR/USD 270=1.36201 271=1000000.00 279=1 269=1 278=A 55=EUR/USD 270=1.36205 271=1000000.00 10=133</p>
  
  <p>and in my config file I have used no data dictionary and set UseDataDictionary=N</p>