Being Loading a large file, Stylepad does not display correctly.

When loading a large file, Stylepad can't seem to render properly. It
render over and over again on the same page which makes
it impossible to read during the loading of the file. However, after the
loading is completed and window has been re-drawn, the file looks fine
and the content can be read without any problems.

It is hard to reproduce this phenomenon but I was able to reproduce it
repeatedly on a PC/AT system (PentiumII 400Mhz, 128MB memory) with a
file size of more than 250KB.

Changing LookAndFeel, same problem occurs.

This phenomenon is found with merlin-beta26
on Solaris2.6(sparc), Solaris7(x86), WinNT and Win98.
This is not occurs with kestrel(fcs-c).

To reproduce:
1) run Stylepad (jdk demo).
2) make a large document. (see a following commnet of **.)
   1) select [File]->[New].
   2) input many characters randomly
   3) save this document (select [File]->[Save]).
3) load this large document.
4) In a moment when Stylepad is loading the document,
  you can see this phenomenon.

* Stylepad can read only a serialized object.
If you do not have a large serialized file for Stylepad,
you need to make a serialized file.

** files for reproducing this phenomenon are attached.
LargeDocument.merlin(247KB) is for merlin.
LargeDocument.kestrel(264KB) is for kestrel.
Stylepad can open these files.