Help! Javascript calculated fields and coded buttons do not function in android Adobe Reader.

I have a job crew form that I have pretty much automated to save myself some time at the end of a job. And as a major part of this improvement my only option known to me to handle in/out time calculations using JavaScript to create a function [Time2Min] to convert the times to calculable values inside the function [TimeDiff] that performs the time difference operation. The code is below:

function Round(nValue, nPrecision) {

// round a number a given precision

return util.printf("%,101." + nPrecision + "f", nValue);

} // end round

function Time2Min(cFormat, sTime) {

sTime = sTime.toLowerCase();

// adjust for 12:MM am

if( (cFormat == "h:MM tt" || cFormat == "hh:MM tt") && ( (sTime.substr(0, 2) == "12" && sTime.substr(6,1) == 'a') || (sTime.substr(0, 2) == "12" && sTime.substr(5,1) == 'a') ) )

   sTime = "00" + sTime.substr(2, sTime.length - 2);

// convert a formatted time string to number of minutes since midnight

// get time object

var oTime = util.scand("mm/dd/yyyy " + cFormat, "01/01/1970 " + sTime);

// convert to milliseconds

var nTime = oTime.getTime();

// convert to milliseconds to minutes and return value

nTime = nTime / (1000 * 60);

// return round to whole minutes

return Number(Round(nTime, 0));

} // end Time2Min

function TimeDiff(cFormat, cTimeIn, cTimeOut) {

var nDiff = 0;

// get the value of the time in and out fields

   var sOut = this.getField(cTimeOut).value;

   var sIn = this.getField(cTimeIn).value;

   // compute if we have both values

   if(sOut != "" && sIn != "") {

      // convert time string to minutes and compute difference

  nDiff = Time2Min(cFormat, sOut) - Time2Min(cFormat, sIn);

      // convert to hours

      nDiff = nDiff / 60;

   }   // end if sOut & sIn

   // return rounded value 

   return Round(nDiff, 2);

   }

Is there any way to accomplish this with simple calculations? Please help.