Description:
As the web site of the plugin (itdamager) developer is down, I uploaded the last version (0.3.2) I have from by backup. The following description is from the google cache of the developer's site.  

Description:
This plugin adds captcha image verification to the WPMU login page. Another tool to stop spam posts that use auto login. This plugin is derived from WPMU-signup-captcha. It doesn't require any core file modifications. Just copy the directory structur