The problem which haunted me long was that my Hero just rebooted on each incoming call when I tried to use the "Auto-answer" mode in my app.
Recently, I've located the kernel bug behind that, but before I even tried to fix it, I found that the fix is already present in some kernels (notably, HTC tattoo).
In all newer HTC kernels it re-appeared both in 2.6.29 and all later versions .
So, I'd be very grateful if you include the patch I'm attaching here. The reason is that I'm now trying to implement some advanced auto-answering features which would be a waste of time as far as they'd work on a single Hero device (and on certain others).
Hope I'm not asking for too much.
Also, please have a look at our project http://code.google.com/p/rvoix: it has a branch by seo who managed to integrate the rvoix call recording in his Espresso ROM for Magic. The in-call recording controls (which are very inconvenient in my app) are built in Phone.apk directly, app settings -- in Settings.apk, etc.
Currently, the branch includes magic-specific smali patches, but he promised to write a review on how to integrate call recording features more conveniently.