How To Add an Image to the Tab Caption

You can include any html you wish in the caption for the tab, so for instance you could include an image link such as <img src='http://myportal.com/images/test.gif'>
You can also include a token that points to the base image folder of your portal by using the [DNN:IMAGEURL] token in the image src. An example would be [DNN:IMAGEURL]/test.gif