12:00am returning as Noon

I have a Time Sheet that I posted about yesterday. "Time In" and "Time Out" fields are converted from time entries to whole hours with 2 decimal places after. They are also rounded off to .25.

My problem is that If a user enters 12:00am in their times, the script recognizes it as noon. i.e. If a user comes in at 11:30am and signs out at 12:30am, it returns "1.00" hour instead of "13.00" hours.

Here's my Document level script:

function TimeDiff(cInName, cOutName) {
// Using a time format of 'h:MM tt' for the start and end times
// create JavaScript date time object for start time
var oStart = util.scand("yyyy/mm/dd h:MM tt", util.printd("yyyy/mm/dd ", new Date()) + this.getField(cInName).value);

// create JavaScript date time object for end time
var oEnd = util.scand("yyyy/mm/dd h:MM tt", util.printd("yyyy/mm/dd ", new Date()) + this.getField(cOutName).value);

// adjust date for start time if start time is later than the end time to the previous day
if (oEnd.valueOf() < oStart.valueOf()) {
oStart.setDate(oStart.getDate() - 1);
} // end adjust start date

// convert Times to minutes
var StartTime = (oStart.valueOf() / (1000 * 60));
var EndTime = (oEnd.valueOf() / (1000 * 60));
// round Times to nearest 15 min
StartTime = Round2Nearest(StartTime, 15);
EndTime = Round2Nearest(EndTime, 15);
// convert Times to hours
StartTime = StartTime / 60;
EndTime = EndTime / 60;
// round Times to 1/100 th of an hour
StartTime = Round2Nearest(StartTime, 0.01);
EndTime = Round2Nearest(EndTime, 0.01);
// compute difference in Times
Diff = (EndTime - StartTime)
// return computed difference in hours
return Diff
} // end TimeDiff
// end document level functions

In a previous incarnation of this form, I solved the problem with this:

var RegExp = /12/;
var RegExp2 = /am/;
var TOText = (this.getField("TimeOut1").value);
if(RegExp.test(TOText))
if(RegExp2.test(TOText))
WholeHours = (WholeHours + 12);
var TIText = (this.getField("TimeIn1").value);
if(RegExp.test(TIText))
if(RegExp2.test(TIText))
WholeHours = (WholeHours + 12);

But I haven't been able to make this work.

Any ideas?