Hi Marco
Take a look at the following document:
http://www.utasker.com/docs/uTasker/uTaskerFileSystem.PDFFrom page 9 the uTasker parameter system is described. This does all such work, including the possibility to temporarily validate a new set of parameters and return an old set if required. There is a practical example of its use and all code for it is available in the uTasker project, which is free for non-commercial use.
Regards
Mark
www.uTasker.com