You might find someone of the community who wants to help you but we do not have any way to properly import this format.
If you are lucky and most of- or even all of these URLs are supported by JDownloader, you could simply let it parse all URLs and look for missing objects - this would not be an "import" anymore then but get you the same results.
If you e.g. also want to "convert" the download paths, download status and so on there will be no way other than coding it.
We are open source - you are free to modify JDownloader to your needs.
-psp-