SNV b36, vermillion 08, jdk1.6.0-beta2-b78, both x86 and sparc

steps:
1. enable AT from launch -> Desktop -> prferences -> Accessibility -> Assisitive Technology Support, and logout, login
2. launch a bugster from terminal by javaws http://bugster
3. try to input username/passwd

expected result:
login bugster

actual result:
can not input anything in the login dialog, and can not input anything in terminal, no keyborad input event can be handled.

Note: this always hanppens on the new login of a user.