In Redmine when you want to export Gantt in a PNG you have this error :

NameError in IssuesController#gantt

no constructor with arguments matching [class org.jruby.RubyNumeric, class org.jruby.RubyFixnum, class magick4j.ImageInfo] on object #<Java::Magick4j::MagickImage:0x1e10f02>

RAILS_ROOT: C:/Depots/redmine
Application Trace | Framework Trace | Full Trace

C:/jruby/lib/ruby/gems/1.8/gems/rmagick4j-0.3.7/lib/rmagick4j/image.rb:190:in `initialize'
C:/jruby/lib/ruby/gems/1.8/gems/rmagick4j-0.3.7/lib/RMagick.rb:1694:in `new_image'
lib/redmine/helpers/gantt.rb:88:in `to_image'
app/controllers/issues_controller.rb:365:in `gantt'
app/controllers/issues_controller.rb:363:in `gantt'
file:/C:/Repos/redmine/tmp/.glassfish/static-cache/gf/glassfish.jar!/rack/adapter/rails.rb:82:in `serve_rails'
file:/C:/Repos/redmine/tmp/.glassfish/static-cache/gf/glassfish.jar!/rack/adapter/rails.rb:109:in `call'
file:/C:/Repos/redmine/tmp/.glassfish/static-cache/gf/glassfish.jar!/rack/handler/grizzly.rb:55:in `call'
:1