There have been many requests on the Autodesk Architectural Desktop Discussion Groups to have tags "built-in" to various objects, rather than having to add a tag after creating the object. The Space Auto Generate Tool, which runs the _AecSpaceAutoGenerate command, does offer the option of automatically tagging the spaces created by that command, but for other objects, like doors, you need to add the tag as a separate step.
For the past three months, Richard Binning has been graciously sharing his extensive knowledge of VBA customization in a series of articles titled "VBA Shortcuts in ADT" in AUGI Hot News that explain how you can create a VBA customization that will automatically tag a door after it is added to your drawing. If this is something you have always wanted to be able to do, or have been waiting for just the right occasion to improve your VBA skills, then I would encourage you to take a look at these articles:
November, 2005 - Part 1
December, 2005 - Part 2
January, 2006 - Part 3
Thanks to Richard for your generosity, and here is hoping that I can find the time to work through these articles myself. If you have not done so already, you will need to become a member of AUGI to access the articles above, but membership is FREE, and provides access to all of the other services offered by AUGI. Sign up now by going here.