History
The original version of this plugin was created by JoeHunk of The Black Company on the Whisperwind server. Earliest comments from him on his forums date back to August of '06. He actively maintained and supported the plugin until May of 2007, when he announced he was ceasing development and support.
Shortly thereafter, Zhinjio took over development and support. Four versions were released using the old codebase, and updating to account for Blizzard patches and user bug reports, ranging from the earliest at end of July in 2007, and the last (version 4.32) released end of September of 2007.
I still have some of the original documentation around from those earlier version. That can be found here. As noted on that page, it is no longer accurate and is included for historical reasons only.
Subsequently, Zhinjio undertook a full rewrite of the code. The first public beta (r70334) was released April 20, 2008. The first gold release (r75175) was release in late May, 2008. The first version compatible with WoW 3.0.2 is now using wowace's new versioning and is up on the site as r122.
This new version was quite a signficant rewrite, and I made an effort to document some of those differences on the Rewrite Differences page.