Netcraft News::
Hosts Disable Movable Type as Comment Spam Slows Servers:
Comment spam attacks on Movable Type weblogs are straining servers at web hosting companies, leading some providers to disable comments on the popular blogging tool. The issues are caused by bugs in MT, forcing publisher Six Apart to recommend configuration changes while it prepares fixes.
The server load issues have affected "a number of web hosts," according to Six Apart's Jay Allen, and are "especially evident in shared hosting environments." Allen said the problems are tied to two bugs that cause Movable Type to rebuild posts even when no pages are being changed, allowing comment spam attacks to tie up server resources. Six Apart is promising a fix within 48 hours.
Comment spam, also known as link spam, is believed to boost a site's ranking in Google, which uses inbound links as a measure of a site's popularity. Spammers are using automated scripts to bombard weblogs with comments that include links to sites offering prescription drugs or porn. While weblogs on all platforms have been affected, Movable Type and its mt-comments.cgi script have become a particular target.
This was mentioned in the article. Poor MT!