This is related to the CR#6808046.

The sample program can be found at /net/cores.central.sun.com/71440698

While user is entering Asian language characters a temporary image to display those typed characters being  introduced to the DOM.
 
Customer's own code which overrides javax.swing.text.html.ImageView  renders this temporary image which obliterated the characters being typed.
 
Customers needs one of two things:
 
1. to know how to avoid rendering the the temporary image.
 
2. a fix which means the temporary image is not seen by their renderer.
 
This is jdk1.5.x on XP specific. Does not occur on Vista.

I've managed to reproduce the problem on 1.5.0_20 and captured the screen at http://vm54.singapore.sun.com/japanese.avi