Stopping a flash caching http requests, without changing the swf itself

I have a flash app which displays a bunch of images from a server, but i need to be able to stop these images from caching (as we are changing them and the client is seeing the older versions, their intranet is caching or something). I know the usual solution is to add a hacky extra parameter, but I don’t have a tag of the code from their version (i know, my bad!) so i’m wondering if there’s a way of externally telling a swf to not cache http requests, or alter the requests in some way. Either javascript or from another hidden swf? Maybe a parameter when embedding the flash object?

Any help would be hugely appreciated!