When you start the timer it will immediately fire an event and then fire an event based on the interval time you specified.

Saying it better, I find more useful a constructor with no initial delay so that I can change the delay as necessary, and then give the start.
Or, as an alternative, the timer should not keep into any account the initial delay if subsequent timer.setInterval(xyz) calls occurr.

 The only way round it is to create a new GTimer object everytime you want to change the interval. This sounds a strange way to do what you want but I cannot override the Timer class behaviour.

1. import guicomponents.*;
   
   GTimer timer;
   
   void setup(){ 
     timer = new GTimer(this, this, "foo", 5000);
     // SOME OTHER STUFF.....
     timer.setInitialDelay(1000);
     timer.setInterval(1000);
     timer.start(3);
   }
   
   void foo() {
     println("timer!!!");
2. }