After much expiermentation i discovered why this project was refusing to show the data.
It has to do with local time settings.
The following code is used to get the task start dates.
var tStartDate = docTask.getItemValueDateTimeArray("StartDate");
var StartDate = tStartDate[0].toString();
What this returns will vary according to the local time settings on the server hosting the code but on my machine in the uk it returns somthing like: 15/06/2011.
The javascript Date constructor will convert this to 6th April 2012. Basically the code will work on machines with a US dat format but not on machines with other formats.