scribu

The Admin dashboard in WP 2.7 has a neat Recent Comments Box, from which you can manage and reply to comments directly. The only problem is that it shows the comment excerpt instead of the entire comment text. This means that you basically have to load another page to view the entire comment.
This simple plugin fixes this issue.
Links: <a href="http://scribu.net/wordpress/full-comments-on-dashboard" rel="nofollow ugc">Plugin News</a> | <a href="http://scribu.net" rel="nofollow ugc">Author’s Site</a>

Full Comments On Dashboard

Show full comments in the Recent Comments box on the admin dashboard.

DZVO

With msHTMLspecialChars can you see all HTML special chars in your comments. 
And you see the complete comments in your dashbord. 
When you actived this plugin can you disabled the default comments widget in your dashbord. 
Bugreport and more informations find your <a href="http://www.zauberpage.de/show-all-html-spezial-chars-in-comments.html" rel="nofollow ugc">here</a>.

ms HTML special Chars in your comments

msHTMLspecialChars - Show all HTML special chars in your comments.

Full Comments On Dashboard vs ms HTML special Chars in your comments