Hi Glenn,
First I would make sure the disitribution point(s) you have didn't have http enabled by default. Go to the web interface -> Management -> Distribution Points and on the distribution server listing make sure the server you are pointing to says No under HTTP. If it is enabled then edit that distribution point, go to the HTTP tab, and uncheck the top box. The reason for this was in the original release of 6 distribution points were set as HTTP enabled by default...
As far as specifying the server to use this is done a couple of ways depending on your setup. If you have Network Segments under the Admin tab you could have a particular server set for each segment. You can also specify the distribution point by editing the machines information in the system. You can force a particular server for a policy by Overriding the Defaults. In the policy under the general tab there is a button in the middle section, lower-right labeled "Override Default Settings for Policy..." and here you can specify servers other than the Master/defaults or even Network Segment defined.
Hope that helps. Whether it was it or not report back if you could...we like to make sure people are taken care of here when we can. =)
Craig E
