Scott Reynolds, scottr@edsi.org reports:

>When I start a PPP session from my shell or from a dt screen, and I exit 
>without killing pppd, my console/terminal hangs.  This has happened both 
>with the console/adb and with tty01 on my system (I have a terminal 
>connected to tty01).  I can logout, but *poof* the keyboard seems to be 
>locked up.

And  Valtteri Vuorikoski, vuori@sci.fi reports:

> Sending something through the serial port occasionally results in
>'panic: kernel jump to zero' and gives a  hung ddb, though more usually 
>it just says 'Bad escape' and hangs (that string is in ddb's parser) 
>on 1.1A kernel from friday or so. Comments ? Did I already post about this ?
>I forget.

Maybe I can add something here that will assist in finding the problem.  
I've been trying to get NetBSD up on my Mac 550 and have seen very 
similar problems.  None of the "standard" Kernels I've tried will boot 
sucessfully on the 550 with a local console.  But, most of them boot with 
a Serial Console however they hang with a "panic: kernel jump to zero".  
The one Kernel I have that boots sucessfully on the 550 in local console 
mode has a hung Keyboard and mouse.  Booted with a Serial Console it 
hangs with a "panic: kernel jump to zero", but the remote keyboard is 
useable.  Seems to me there is a connection here between the ADB keyboard 
hang promlems I've seen on the 550 and the Serial Console errors that 
Scott and Valtteri are reporting.  Sure give me hope that very soon now I 
might have a working NetBSD for my 550 thanks to the efforts of many hard 
workers on this project.

-Bob