FULL PRODUCT VERSION :
1.6.0_23

ADDITIONAL OS VERSION INFORMATION :
e.g. Windows XP Version 5.1.2600 but
reproducible on all major supported OS versions, WIndows XP, Vista, Windows 7 and also on Linux variants.


EXTRA RELEVANT SYSTEM CONFIGURATION :
all major windows platforms, also linux platforms, reproduced with all major browsers (IE,Firefox, Chrome) using the latest Sun/Oracle Java-Plugin 1.6.0_23 (and also some older versions)

A DESCRIPTION OF THE PROBLEM :
We have a web-application that uses a Java Applet to visualize graphical information. There are icons shown on a canvas, these Icons have specific tooltips. The tooltip is generated by overriding the "getToolTipText(MouseEvent e)" method which simply generates/returns a specific tooltip depending on the current mouse position (pixels).

on initial page and applet load everything works but as soon as the page is refreshed (e.g. user submits a form located on this web-page and changes visualisation parameters, the page + applet is re-loaded with different parameters)

after this refresh, the tooltips are not visible any more. There is a small box visible (size about 2 or 3 times 2 or 3 pixels) next to the mouse cursor which obviously should be the tooltip-box showing the whole text.

debugging the applet shows that "getToolTipText" is invoked and the correct text is returned, but the visualisation somehow within AWT/Swing in the applet is broken.

identical code works without any problem under JDK/JRE 1.6.0_19 for instance.




STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
write a java applet within a html page, embed with <object> tag and some parameters that are controlled with a html form contained in the same page.

the java applet should generate different tooltips based on mouse cursor position by overriding "getToolTipText(MouseEvent e)" method.

open the web-page and move mouse cursor over the applets canvas/JFrame. tooltips are shown.

change some applet params via the contained html-form and submit the form (= refresh the page)

move again mouse cursor over the applets canvas/Jframe --- tooltip visualisation fails, no tooltip is shown any more.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
the tooltip text should be shown correctly also after page refresh.
ACTUAL -
no tooltip text is visible. only a small (only some pixel size) box can be found next to the mouse cursor, seems that this is only a corner of the real tooltip box that is not visible for some reason when the page/applet is refreshed.



ERROR MESSAGES/STACK TRACES THAT OCCUR :
no error message is shown, also nothing in java console.

REPRODUCIBILITY :
This bug can be reproduced always.