Msg#: 3520664 posted 4:49 am on Dec 5, 2007 (gmt 0)
There are actually two PTR records for addresses in that range; If your server checks only the first (which appears to be a CNAME), then it may fail rDNS verification. The second record points to hotmail.com
Based on this and what I've seen of their robots.txt and on-page robots meta-tag handling, I have to agree with your assessment.
[edited by: jdMorgan at 4:49 am (utc) on Dec. 5, 2007]
Msg#: 3520664 posted 5:30 am on Dec 6, 2007 (gmt 0)
Now you know why I use a combination of methods.
Cached reverse DNS lookups for a quick test for bot validity and if that fails I check to see if it at least belongs to a range owned by the company associated with the bot and do this for Google, Yahoo, Microsoft, Ask, Gigablast, etc.
[edited by: incrediBILL at 5:30 am (utc) on Dec. 6, 2007]