Redmine

I think the solution to the bug is not perfect. I update a wiki page with a lot of new content while others edit the page simultaneusly. However, when I save it, the page tells me I can't do this. What I can do is to leave the page and edit it again. I think this will cost editors much time especially when the new content scatterd in the page and there may be many editors update the same page at the same time.

I suggest to fix the problem with solution 2:
2) Make the "Lock" system work so that a user would have to "break the lock" in order to edit the wiki. (Thus alerting a user that they might not want to edit the wiki at this present moment, but at the same time allowing a lock to be broken if a user has forgotten to remove it after their edit has been saved).

Redmine version details:
Redmine version 2.2.3
Ruby version 1.9.3p194 (2012-04-20 revision 35410)[i686-linux]
RubyGems version 1.5.2
Rails version 3.2.12
Operating system: centos 5.5 (2.6.18-194.el5PAE)
Database: mysql-devel-5.0.95-5.el5_9
Database adapter mysql2
Ruby-aware server used: Mongrel

Current Problem:
If two managers (or users with the "Edit wiki pages" permission) edit a wiki in the following way this results in a catastrophic error:
Manager 1 - Opens wiki in edit mode
Manager 2 - Opens wiki in edit mode
Manager 2 - Makes changes to wiki
Manager 2 - Saves wiki
Manager 1 - Makes changes to wiki
Manager 1 - Saves wiki

Manager 1 now gets an explanatory error page and retain the users edited text. The lock system (achieved with the "Protect wiki pages" permission) seems to be a step in the right direction, however this does not prevent another user with the same permission from editing the wiki and quite often we find they neglect to notice the "locked" icon in the top right-hand corner of the wiki before clicking "edit".

ada sun's suggestion looks reasonable. We use Redmine Wiki for preparing grant applications so the situation when multiple people try to edit the same page at the same time is not rare.