Documentation for Confluence 5.4.
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Title: Configuring Captcha for Failed Logins  
Author: Sarah Maddox [Atlassian] Apr 27, 2010
Last Changed by: Rachel Robins [Atlassian Technical Writer] Feb 21, 2013
Tiny Link: (useful for email) https://confluence.atlassian.com/x/cIPuD
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    Page: Configuring Confluence Security
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