Missing dictionary for spell check prevents program start

[Jonathan Corwin]

From: http://openlp.org/en/forums/openlp_20/general_discussion/194_bzr1419_cant_launch_on_ubuntu_lucid.html

Program fails to start on a Ubuntu system due to spell check functionality, looking at the trace: http://pastebin.com/Cgjk14VN

Traceback (most recent call last):
  File "/usr/bin/openlp", line 299, in <module>
    main()
  File "/usr/bin/openlp", line 293, in main
    sys.exit(app.run())
  File "/usr/bin/openlp", line 187, in run
    self.clipboard())
  File "/usr/lib/pymodules/python2.6/openlp/core/ui/mainwindow.py", line 606, in __init__
    self.pluginManager.find_plugins(pluginpath, self.pluginHelpers)
  File "/usr/lib/pymodules/python2.6/openlp/core/lib/pluginmanager.py", line 102, in find_plugins
    plugin = p(plugin_helpers)
  File "/usr/lib/pymodules/python2.6/openlp/plugins/custom/customplugin.py", line 54, in __init__
    self.edit_custom_form = EditCustomForm(self)
  File "/usr/lib/pymodules/python2.6/openlp/plugins/custom/forms/editcustomform.py", line 54, in __init__
    self.editSlideForm = EditCustomSlideForm(self)
  File "/usr/lib/pymodules/python2.6/openlp/plugins/custom/forms/editcustomslideform.py", line 45, in __init__
    self.setupUi(self)
  File "/usr/lib/pymodules/python2.6/openlp/plugins/custom/forms/editcustomslidedialog.py", line 37, in setupUi
    self.slideTextEdit = SpellTextEdit(self)
  File "/usr/lib/pymodules/python2.6/openlp/core/lib/spelltextedit.py", line 52, in __init__
    self.dictionary = enchant.Dict(u'en_US')
  File "/usr/lib/pymodules/python2.6/enchant/__init__.py", line 475, in __init__
    self._switch_this(broker._request_dict_data(tag),broker)
  File "/usr/lib/pymodules/python2.6/enchant/__init__.py", line 260, in _request_dict_data
    self._raise_error(eStr % (tag,),DictNotFoundError)
  File "/usr/lib/pymodules/python2.6/enchant/__init__.py", line 215, in _raise_error
    raise eclass(default)
DictNotFoundError: Dictionary for language 'en_US' could not be found
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