Simple date and time manipulation

[tsk1979]

I have already looked at Date:Manip, and its very powerful, as well as slow. MY requirement is a bit simple. I am writing a gpx file, and every trkpnt entry requires a date time in the following format

<time>2011-01-01T00:00:03Z</time>

I will be writing track points inside a loop, and in every entry I will be incrementing the time by 1 hour 2 minutes and 3 seconds. I am planning to write over a 1000 trackpoints. Since I do not require all the complications of Date:Manip, is there something simpler I can use A typical algo I will do

for (i from 1 to 1000)
print <header>
print "$date";
$date = $date + "01:02:33";
endfor