1. Version number: 1.0.9
2. Operating system: Mac OS X 10.5.8 running on a 2.66 GHz Intel iMac
3. Code:

void setup() { size(100, 100); }
void draw() { background(0); }
void mouseClicked() { println("mouseX=" + mouseX + " mouseY=" + mouseY); }

4. n/a
5. Details: When I click on various locations in the window, it prints
"mouseX=0 mouseY=0".
It should be printing out the location of my click.
When I drag the mouse and release in the lower left, it prints, "mouseX=99
mouseY=99".
It would appear that mouseX and mouseY are only being updated on mouseRelease.

Please help!

That code is working fine here, it may be a bug in Apple's Java
implementation. Use mousePressed() instead and see how that works.

I just noticed that I am having mouse even trouble in other applications,
like the Finder and Firefox. It may be a problem with my mouse hardware,
mouse driver, or something else even worse. This bug should be removed,
sorry about that.