ga hidden fields

<form id="someContactForm" onsubmit="populateHiddenFields(this);"> <!-- on submit populate the google analytic fields -->

   <!-- all the other other contact input fields -->

   <!-- now the google analytis hidden fields -->
   <input type="hidden" name="source" />
   <input type="hidden" name="medium" />
   <input type="hidden" name="term" />
   <input type="hidden" name="content" />
   <input type="hidden" name="campaign" />
   <input type="hidden" name="segment" />
   <input type="hidden" name="numVisits" />

</form>

<script type="text/javascript">
//
// This is a function that I "borrowed" from the urchin.js file.
// It parses a string and returns a value.  I used it to get
// data from the __utmz cookie
//
function _uGC(l,n,s) {
 if (!l || l=="" || !n || n=="" || !s || s=="") return "-";
 var i,i2,i3,c="-";
 i=l.indexOf(n);
 i3=n.indexOf("=")+1;
 if (i > -1) {
  i2=l.indexOf(s,i); if (i2 < 0) { i2=l.length; }
  c=l.substring((i+i3),i2);
 }
 return c;
}

//
// Get the __utmz cookie value. This is the cookies that
// stores all campaign information.
//
var z = _uGC(document.cookie, '__utmz=', ';');
//
// The cookie has a number of name-value pairs.
// Each identifies an aspect of the campaign.
//
// utmcsr  = campaign source
// utmcmd  = campaign medium
// utmctr  = campaign term (keyword)
// utmcct  = campaign content
// utmccn  = campaign name
// utmgclid = unique identifier used when AdWords auto tagging is enabled
//
// This is very basic code. It separates the campaign-tracking cookie
// and populates a variable with each piece of campaign info.
//
var source  = _uGC(z, 'utmcsr=', '|');
var medium  = _uGC(z, 'utmcmd=', '|');
var term    = _uGC(z, 'utmctr=', '|');
var content = _uGC(z, 'utmcct=', '|');
var campaign = _uGC(z, 'utmccn=', '|');
var gclid   = _uGC(z, 'utmgclid=', '|');
//
// The gclid is ONLY present when auto tagging has been enabled.
// All other variables, except the term variable, will be '(not set)'.
// Because the gclid is only present for Google AdWords we can
// populate some other variables that would normally
// be left blank.
//
if (gclid !="-") {
      source = 'google';
      medium = 'cpc';
}
// Data from the custom segmentation cookie can also be passed
// back to your server via a hidden form field
var csegment = _uGC(document.cookie, '__utmv=', ';');
if (csegment != '-') {
      var csegmentex = /[1-9]*?\.(.*)/;
      csegment    = csegment.match(csegmentex);
      csegment    = csegment[1];
} else {
      csegment = '(not set)';
}

//
// One more bonus piece of information.
// We're going to extract the number of visits that the visitor
// has generated.  It's also stored in a cookie, the __utma cookis
//
var a = _uGC(document.cookie, '__utma=', ';');
var aParts = a.split(".");
var nVisits = aParts[5];

function populateHiddenFields(f) {
      f.source.value  = source;
      f.medium.value  = medium;
      f.term.value    = term;
      f.content.value = content;
      f.campaign.value = campaign;
      f.segment.value = csegment;
      f.numVisits.value = nVisits;
}
</script>