Tested with Merlin b60 on Solaris7/8 Sparc using ATOK8 for Japanese imput methoed (*all required paches are installed on the machine).
(This problem is seen from b59.)

Japanese input mode can not work well after inputting some Japanese characters and then, making the series of "Edit" actions.

To reproduce,

1. Launch StylePad (it is reproducible with Notepad)
2. Press "ctrl + space" to make Japanese input mode available.
3. Enter some Japanese characters.
4. Just click one of the menu of Stylepad.
   Then, Japanese input mode is turned off.
5. Press Ctrl + Space to turn on Japanese input mode.
   Then, the status window for Japanese input mode does not appear.
6. Enter some Japanese characters.
   Then, the characters are not displayed until they are comitted.
7. Click one of the menu again.
   Then, the menu does not work (can not be selected) and
   no characters are accepted in inptting area of Stylepad.
   Stylepad is hung and the process needs to be killed (Ctrl C does not work).



The problem is not reproducible with ATOK12 and Wnn.

If before step 4), pressing "ctrl + space" to turn off Japanese IM,
the problem does not occur.

I add 4368048 to "See also".
This is reproducible with the same kind of the operations (please see the comments in 4368048 updated by miki.tokunaga@japan for more detail).