I was able to hack 1.5.2's pluggable functions to allow comment notification (see this thread for background. Bottom line is Yahoo requires that the e-mail WP sends to have a "from" from your own domain.
I have upgraded to 2.0 and everything works great except now I have to hack pluggable functions again in order to get comment notification. Can anyone help. I've tried a few things but nothing works, and the 2.0 file is a lot different from the 1.5.2 file.
Just FYI, I know Yahoo comes with a stock 2.0 installation but they require you put it into an individual directory, which I didn't want, and they also do not provide any mechanism for importing your old posts into their new install (they create a seperate SQL database and do not give you a password to it).
P.S, I know there is a plugin that will fix this, but the plugin also requires you to edit the core code. I'd rather just edit the code alone and not have to depend on a plugin.