My blog was locked because of some spam-bot. Blogger was kind enough to send me an email:
This system has detected that your blog has characteristics that resemble spam. Since you're an actual person reading this, your blog is probably not a spam blog. Automated spam detection is inherently fuzzy, and we sincerly (sic) apologize for this erroneous result.This next part was reassuring:
You won't be able to publish posts to your blog until we review your site and verify that it is not a spam blog.
We'll take a look at your blog and unlock it in less than one business day.Well, it actually took 3 business days. Thanks, Blogger.