CCK + GMap + Location Module
I was wrong. I thought I need to create separate field to hold location information. While that step will produce no error, the node map won’t show off. To work with Location module, you only need to enable Location support for each content type.
Voila! Now you can show the map by using Location block. Yes, no embeded map.
System:
Drupal 6 + GMap + Location module