This is my current init setup.
It doesn't seem to matter what settings I use.
uses_tiny_mce :class => 'mceEditor', :options => { :theme
=> 'advanced', :theme_advanced_layout_manager =>
'SimpleLayout', :theme_advanced_toolbar_location => 'top',
:theme_advanced_buttons1 => 'bold, italic, underline,
strikethrough, separator, bullist, numlist, separator, justifyleft,
justifycenter, justifyright, justifyfull, separator, outdent,
indent, separator, link, unlink, separator, blockquote, code,
image, separator, formatselect', :theme_advanced_buttons2 => '',
:theme_advanced_buttons3 => '', :content_css => '',
:apply_source_formatting => 'true', :remove_redundant_brs =>
'true', :cleanup => 'true', :convert_newlines_to_brs =>
'false', :force_br_newlines => 'false', :force_p_newlines =>
'true' }