Redmine安装失败，很多时候是因为安装环境不对。Redmine官网列出了安装需求，见：http://www.redmine.org/projects/redmine/wiki/RedmineInstall
| Redmine version | Supported Ruby versions | Required Rails version | Required Rack version |
|---|---|---|---|
| current trunk | ruby 1.8.6, 1.8.7 | Rails 2.3.11 | Rack 1.1.0 |
| trunk from r2887 to r4903 | ruby 1.8.6, 1.8.7 | Rails 2.3.5 | Rack 1.0.1 |
| trunk from r2493 to r2886 | ruby 1.8.6, 1.8.7 | Rails 2.2.2 | |
| trunk before r2493 | ruby 1.8.6, 1.8.7 | Rails 2.1.2 | |
| 1.1.x | ruby 1.8.6, 1.8.7 | Rails 2.3.5 | Rack 1.0.1 |
| 1.0.x | ruby 1.8.6, 1.8.7 | Rails 2.3.5 | Rack 1.0.1 |
| 0.9.x | ruby 1.8.6, 1.8.7 | Rails 2.3.5 | Rack 1.0.1 |
| 0.8.x | ruby 1.8.6, 1.8.7 | Rails 2.1.2 |
