DNS errors when performing http test

I keep getting DNS errors when performing the HTTP test against two W2k3 servers. They are sporadic, and they recover almost immediately. I am using http://host.domain.local for internal DNS structure. Is this the problem? No other HTTP test are failing, such as checking company website.

David Gilmore Consultant Stenhouse Consulting, LLC. 4 Traverse St Providence, RI 02906 401.453.6900 401.454.7581 (fax)