Redmine

With IE8 (Internet Explorer 8), subject strings listed in subtasks area will be cleared with mouse selection.

Here are steps to reproduce:

1. Show an issue that have subtasks with IE. (e.g. http://demo.redmine.org/issues/31577)
2. Select some subject strings in subtasks with mouse (e.g. subject string 'Test ' in subtask 31579).
3. release the left-button. Selected strings will be disappeared.

Followings are my environment.

Ruby version              1.8.7 (i386-solaris2.10)
RubyGems version          1.3.1
Rack version              1.0
Rails version             2.3.5
Active Record version     2.3.5
Active Resource version   2.3.5
Action Mailer version     2.3.5
Active Support version    2.3.5
Edge Rails revision       unknown
Application root          /tank/www/redmine-1.0.1
Environment               production
Database adapter          mysql
Database schema version   20100819172912

The function clearDocumentSelection() in public/javascripts/context_menu.js uses document.selection.clear() for IE. I assume this might be the cause.