Patch adding support for spam detection using honeypot/akismet

Here is a patch against version 3.4.3 of the plugin that adds a honeypot field and use of Akismet (if installed) for spam detection.

http://pastebin.com/0kJR81gN

It worked for me with version 3.5.1 of WordPress.

http://ww.wp.xz.cn/extend/plugins/contact-form-plugin/