Preloading dynamicly loaded jpegs?

Hi I’m new to these boards.
I have been having real difficulty working out how to create a preloader for dynamicly loaded jpegs. I am fairly new to flash and this is probably a really obvious question, but is it possable to create a simple preloader for this situation. I have built a flash site that gets all the data from mysql via php, so I want to be able to code a preloader that can be used when ever a new piece of external content is loaded. All the tutorials I have found work for movieclips but they don’t seem to work when loading jpegs. If any one knows a good tutorial, or explaination of preloading they could point me to I would very much appriciate it. If it would help if I posted up the code from my site, lemmie know.

Hope this isn’t to silly a question!
max