title: Incorrect NumInGroup count for repeating group QuickFix
body: <p>I am unable to parse this market data incremental refresh message(fix 4.3):</p>
  
  <pre><code>8=FIX.4.3|9=187|35=X|34=4|49=XDEMO|52=20130224-22:31:05.283|56=demo310262=A|268=2|279=2|269=0|278=0014vd32|55=EUR/USD|290=1|64=20130227|279=0|269=0|278=0014vdb2|270=1.31934|271=1000000|290=1|546=3|10=124
  </code></pre>
  
  <p>Quickfix/j gives me the following:</p>
  
  <blockquote>
    <p>quickfix.FieldException: Incorrect NumInGroup count for repeating group, field=268</p>
  </blockquote>
  
  <p>I know that is a repeating group issue, but I not quite sure how to change my spec in order to parse this message.</p>