Rake提示uninitialized constant Rake::DSL解决办法

环境：Ruby 1.9.1/Rails 3.0.9/Rake 0.9.2

在运行rake db:create的时候提示

1.rake aborted!  
2.uninitialized constant Rake::DSL  
3./usr/local/ruby/lib/ruby/1.9.1/rake.rb:2482:in `const_missing'  
4./usr/local/ruby/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/tasklib.rb:8:in `<class:TaskLib>'  
5./usr/local/ruby/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/tasklib.rb:6:in `<module:Rake>'  
6./usr/local/ruby/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/tasklib.rb:3:in `<top (required)>'  
7./usr/local/ruby/lib/ruby/gems/1.9.1/gems/rdoc-3.6.1/lib/rdoc/task.rb:37:in `require'  
8./usr/local/ruby/lib/ruby/gems/1.9.1/gems/rdoc-3.6.1/lib/rdoc/task.rb:37:in `<top (required)>'  
9./usr/local/ruby/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks/documentation.rake:2:in `require'  
10./usr/local/ruby/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks/documentation.rake:2:in `<top (required)>'  
11./usr/local/ruby/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks.rb:15:in `load'  
12./usr/local/ruby/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks.rb:15:in `block in <top (required)>'  
13./usr/local/ruby/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks.rb:6:in `each'  
14./usr/local/ruby/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/tasks.rb:6:in `<top (required)>'  
15./usr/local/ruby/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/application.rb:215:in `require'  
16./usr/local/ruby/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/application.rb:215:in `initialize_tasks'  
17./usr/local/ruby/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/application.rb:139:in `load_tasks'  
18./usr/local/ruby/lib/ruby/gems/1.9.1/gems/railties-3.0.9/lib/rails/application.rb:77:in `method_missing'  
19./usr/local/sharephoto/Rakefile:7:in `<top (required)>'  
20./usr/local/ruby/lib/ruby/1.9.1/rake.rb:2373:in `load'  
21./usr/local/ruby/lib/ruby/1.9.1/rake.rb:2373:in `raw_load_rakefile'  
22./usr/local/ruby/lib/ruby/1.9.1/rake.rb:2007:in `block in load_rakefile'  
23./usr/local/ruby/lib/ruby/1.9.1/rake.rb:2058:in `standard_exception_handling'  
24./usr/local/ruby/lib/ruby/1.9.1/rake.rb:2006:in `load_rakefile'  
25./usr/local/ruby/lib/ruby/1.9.1/rake.rb:1991:in `run'  
26./usr/local/ruby/bin/rake:31:in `<main>'

解决方法：

打开RakeFile文件，在require 'rake'上面加入

require 'rake/dsl_definition'