BOUML is a free UML 2 tool box allowing you to specify and generate 
code in C++, Java, Idl, Php and Python.

Bouml documentation provides a complete user manual in HTML format, 
and context sensitive help using F1 key from inside the application.

To configure for use after installation:

You may use the documentation as a complete HTML manual by pointing your 
browser to "file:///usr/share/bouml/docs/index.html

To configure context sensitive help within the application, from the
drop menus select:
  Miscellaneous >> Set environment (dialog opens)
  Set "Manual path" = /usr/share/bouml/docs/