Redmine

I updated my redmine codebase from 0.9 stable branch to newest trunk by running svn switch command:" svn switch http://redmine.rubyforge.org/svn/trunk", rake db:migrate and then restart the server.
Everything runs well except the related to issue seems to be broken, after I add/delete an related issue, the page won't show me the effect, I had to refresh manually to see my change, I guess it's because the AJAX failed.
OK, then I gave up using trunk, and tried the 1.1 stable version by 'svn switch http://redmine.rubyforge.org/svn/branches/1.1-stable', restarted server, great, it works!
So the problem is existed in trunk, not in stable branch.

About my 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
Edge Rails revision unknown
Application root /www/html/redmine
Environment production
Database adapter mysql
mysql Ver 14.12 Distrib 5.0.77, for redhat-linux-gnu (x86_64) using readline 5.1