Unexpected behaviour of Ctrl+Z after use of "[" shortcut

[GoogleCodeExporter]

Assume the option of using "[" to enclose next sexp in "()" is activated
(from Window > Preferences > Lisp > Editing). 

Follow the instructions bellow to reproduce the behaviour. After each
instruction is an illustrations of its output, where the symbol "|"
represents the cursor position.

1. Put the cursor right before a certain sexp (0, for example):
    |0
2. press "[", you'll get something like:
    (| 0)
3. press Ctrl+Z to undo the previuos action, and you'll get:
    0|
   with the sexp being selected!

The undo action (Ctrl+Z) should put the editor in its previous state, that was:
    |0
with the cursor before the sexp (where it originally was) and without
selecting the sexp at all.

So there are two problems after using "[" + undo:
 - the position of the cursor is changed and
 - the sexp is selected.

This was observed with Cusp 1.0.414
(early released at cusp-development group, see
http://groups.google.com/group/cusp-development/browse_thread/thread/15a3a92e9e4
2fcfb)
and Eclipse 3.5.0 on Ubuntu Linux.

Original issue reported on code.google.com by marcioma...@gmail.com on 13 Sep 2009 at 2:08