Redmine

Mmh, I think I've been doing what you are describing for a long time without having any problem. Trying just now, if you can read this, I wasn't able to reproduce here :-)

Some more detail about your setup? (see SubmittingBugs)

A user downstream reported it us. We're using Redmine trunk - pretty close to HEAD.

About your application's environment
Ruby version              1.8.7 (x86_64-linux)
RubyGems version          1.3.5
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
Environment               production
Database adapter          mysql
Database schema version   20100429224143

About your Redmine plugins
Redmine Vote plugin        0.0.2
Google Analytics plugin    0.1.0
Markdown Extra formatter   0.0.2
Bots filter                1.02
Redmine Simple Support     0.1.0
Redmine Hudson plugin      1.0.1.1
Markdown formatter         0.0.1

Just tried with JS off to see if that could be the cause of the problem, but that doesn't cause the error you mentioned.

Can your user reproduce it, and if yes, could you capture the log snippet pertaining to that?

James, have you eben able to reproduce this in any menaningful way, or to find some error log or trace?