Article ID: 2466018 - View products that this article applies to.
Consider the following scenario:
Note By default, the crawl target feature is not used for host header site collections. This feature is controlled by the AllowHostHeaderCrawlTarget search application setting.
To resolve this issue, apply this following hotfix package:
(http://support.microsoft.com/kb/2459257/ )Description of the SharePoint Server 2010 Cumulative Update Server Hotfix Package (MOSS server-package): December 31, 2010
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.