'Spoof US English Browser' option cannot be turned off

I have Torbutton 1.1.18alpha running on Firefox 3.0b5 and the 'Spoof US English Browser' cannot be turned off. I have deselected it form the options, but still every time I toggle Tor or open the preferences panel of Torbutton all other languages are removed leaving only 'en-US' and 'en'.

[Automatically added by flyspray2trac: Operating System: All]

Trac:
Username: deepdraft

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