Unexpected behaviour when indenting a bullet list

Type the following into the editor:

one

• two
  • three

Highlight all, and click the button to indent.

Expected - all lines are indented equally:

one

• • two
    • three

Actual - the level 2 bullet is not further indented:

one

• • two
  • three

(Originally reported at https://answers.atlassian.com/questions/21735/occupy-confluence-markup-provide-a-wysiwyg-xhtml-markup-editor-to-edit-the-markup-source-of-confluence-4-wiki-pages/41632)