put this in your initializers directory

mceoptions.rb

# getting nil.merge errors in production when overriding a controller in CE?

AppConfig ||= OpenStruct.new
AppConfig.default_mce_options = {
  :theme => 'advanced',
  :browsers => %w{msie gecko safari},
  :theme_advanced_layout_manager => "SimpleLayout",
  :theme_advanced_statusbar_location => "bottom",
  :theme_advanced_toolbar_location => "top",
  :theme_advanced_toolbar_align => "left",
  :theme_advanced_resizing => true,
  :relative_urls => false,
  :convert_urls => false,
  :cleanup => true,
  :cleanup_on_startup => true,  
  :convert_fonts_to_spans => true,
  :theme_advanced_resize_horizontal => false,
  :theme_advanced_buttons1 => %w{bold italic underline separator justifyleft justifycenter justifyright indent outdent separator bullist numlist separator link unlink image media separator undo redo code},
  :theme_advanced_buttons2 => [],
  :theme_advanced_buttons3 => [],
  :plugins => %w{media preview curblyadvimage inlinepopups safari autosave},
  :plugin_preview_pageurl => '../../../../../posts/preview',
  :plugin_preview_width => "950",
  :plugin_preview_height => "650",
  :editor_deselector => "mceNoEditor",
  :extended_valid_elements => "img[class|src|flashvars|border=0|alt|title|hspace|vspace|width|height|align|onmouseover|onmouseout|name|obj|param|embed|scale|wmode|salign|style],embed[src|quality|scale|salign|wmode|bgcolor|width|height|name|align|type|pluginspage|flashvars],object[align<bottom?left?middle?right?top|archive|border|class|classid|codebase|codetype|data|declare|dir<ltr?rtl|height|hspace|id|lang|name|style|tabindex|title|type|usemap|vspace|width]",
	:media_strict => false    
  }
  
AppConfig.simple_mce_options = {
  :theme => 'advanced',
  :browsers => %w{msie gecko safari},
  :cleanup_on_startup => true,
  :convert_fonts_to_spans => true,
  :theme_advanced_resizing => true, 
  :theme_advanced_toolbar_location => "top",  
  :theme_advanced_statusbar_location => "bottom", 
  :editor_deselector => "mceNoEditor",
  :theme_advanced_resize_horizontal => false,  
  :theme_advanced_buttons1 => %w{bold italic underline separator bullist numlist separator link unlink image},
  :theme_advanced_buttons2 => [],
  :theme_advanced_buttons3 => [],
  :plugins => %w{inlinepopups safari curblyadvimage}
  }