yaboot error on ppc instalation on external HD

[altern]

>>i am not sure if anyone has already talked about this issue.
>>I am trying to install ubuntu on a powerbook 12". I am using an external 
>>usb 160G HD and i am trying to install ububtu there (i am not confident 
>>yet to install it on my main HD).
>>I get an error saying that yaboot cannot be installed.
> 
> 
> yaboot doesn't understand how to find the OpenFirmware path to external
> disks yet, so booting off them won't work. There's an open bug about
> this.

this is a pitty. so there is no workaround this yet.
Then could anyone describe how to install ubuntu on a powerpc with osx 
panther so that you get dual boot? ideally i would like to be able to 
acccess a data partition with both systems or to access from ubuntu the 
osx partition. maybe there is some wiki about this?

thanks

-- 
enrike