As you may have seen earlier, I’d picked up development of the Hebrew Date plugin from KosherJava. Today, I’m officially releasing version 1.0.0. Much of the logic is rewritten, but most of the credit goes to KosherJava!
To install, download the plugin (from here),activate, and enjoy!
There are lots of fun config options under the options tab. Specifically, in order to use the sunset correction (evening dates will have the correct Hebrew date), you need to provide a latitude and longitude.
Please note that this code has only been tested on WP 2.0+. It may work on 1.5, but I’m not sure.