On Cache tab, push "View files in Cache" button.
You can see "Java Plug-in Cache Viewer" dialog and the box chars
for non-ascii chars are in the type/date-time columns in L10N gui
if it has some caches. This problem occurs only on Solaris/Windows
but not on Linux.

This problem still remain since 1.4.0 (merlin) release.
(see 4631651)