migrating from yesod 0.8 to 0.9

I have just upgraded to yesod 0.9 and I am getting this error below, which is not mentioned in the upgrade guide in the Michael's announcement (http://www.yesodweb.com/blog/2011/08/yesod-0-9-release-candidate):

config\Settings.hs:27:18开发者_StackOverflow社区:
    Could not find module `Text.Lucius':

how to fix this?

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needed to addshakespeare-cssto my.cabalfile.