The freeware PAD (Portable Application Description) file editor for Mac OS X
Apimac PAD Editor is a PAD (Portable Application Description) file editor. PAD files help software authors to provide product descriptions and specifications to online sources in a standard way, using a standard data format that allow webmasters and program librarians to automate program listings. You can find more info about PAD at the ASP's site.
Unlike other PAD editors, Apimac PAD Edit is fully XML compliant and fully PAD specifications compliant. The program uses a smart engine to directly obtain information about the PAD files from the PAD specification XML file (padspec.xml), including names, descriptions, field length, allowed characters and format. A window will let you know instantaneously if what you wrote is valid according to the specifications, or not. There's no need to use external PAD validation services, the program checks for the validity of fields every time you leave one.