asset-pipeline - 在 JRuby 中预编译 ejs 资产时无法复制 TrueClass

Question

在 JRuby 中运行 rake assets:precompile 时，我得到以下回溯：

can't dup TrueClass
  (in C:/tripwire/app/assets/templates/alert_histories/index.jst.ejs.slim)
org/jruby/RubyKernel.java:1908:in `dup'
org/jruby/RubyArray.java:1613:in `each'
org/jruby/RubyArray.java:1613:in `each'
org/jruby/RubyArray.java:1613:in `each'
org/jruby/RubyArray.java:1613:in `each'
org/jruby/RubyProc.java:249:in `call'
org/jruby/RubyArray.java:1613:in `each'
org/jruby/RubyProc.java:249:in `call'
org/jruby/RubyArray.java:1613:in `each'
org/jruby/RubyArray.java:1613:in `each'
org/jruby/RubyKernel.java:1046:in `load'
Tasks: TOP => assets:precompile:primary
(See full trace by running task with --trace)
rake aborted!
Command failed with status (1): [c:/jruby-1.7.2/bin/jruby.exe c:/jruby-1.7....]
org/jruby/RubyProc.java:249:in `call'
org/jruby/RubyProc.java:249:in `call'
org/jruby/RubyArray.java:1613:in `each'
org/jruby/RubyArray.java:1613:in `each'
org/jruby/RubyKernel.java:1046:in `load'
Tasks: TOP => assets:precompile
(See full trace by running task with --trace)

有没有其他人遇到过这个？任何建议将不胜感激

以下是相关 gem 的版本：

 ejs (1.1.1)
 rails (3.2.8)
 rake (10.0.3)
 jruby 1.7.2 (Ruby 1.9)