title: yii relations on multiple database connections
body: <p>I am using two database connections in Yii. 
  One contains a table with the office name that I would like to be able to use as a related field for a model in a different database in a grid-view so the filters will work </p>
  
  <p>I have used virtual attributes and a get method which will give me the name I require in the grid . However the filter does not work. </p>
  
  <p>Is there a way to use relations in the model with multiple databases ?
  Or is there something I can put in the search method that will work ? </p>