These binaries were once hosted on my Dropbox's public folder, but Dropbox is now removing support for public folders. Thus, I am now uploading all of the previous versions here. (The thread on bukkit.org is locked and I cannot update the link there.) The un-suffixed version is the same file as MCSignOnDoor.1.9.p60.jar.
This project is no longer maintained by myself. Others (names escape me) have asked previously to update the project for the latest versions of Minecraft. Go find them if you want the latest versions supporting the latest APIs.
Yes, you may fork this project, as long as you follow the Creative Commons license and attribute me for the original name and code. (If you create it from scratch, I guess that license doesn't apply. I saw a project of similar scope over on the npm; good on them, node.js is awesome.)