1. type your text.
2. duplicate text object.
3. import bitmap img or whatever object you're using as background.
4. duplicate background.
5. postion text object over background.
6. select text object and background > object > clip > set. (I don't believe it is necessary to convert text to path first, but if this doesn't work then do that.)
7. select your clipped background and move to top of image using home key or object>bring to top.
8. select the other text object and apply blur using the fill and stroke dialog. then move it behind the clipped background.
You can get more sophisticated effects but this should work.
edited to add the quick result ii got with the above technique. I did add a second "shadow" in white b/c the text was getting lost in the image. Still not perfect, but better.
