First install of powerpc freebsd install problem

[Adrian Kubok]

Hello.
I'm trying to install freebsd powerpc 10.0 BETA3 on powerbook g3  
(500MHz/1Gb)
Bootcd hangs with "mountroot>" prompt. bootonly and disc1 gives same error


Mounting from cd9600:/dev/iso9660/FREEBSD_INSTALL failed with error 19.

mountroot> cd9660:acd0
Trying to mount root from cd9660:acd0 []
mountroot: waiting for device acd0 ...
Mounting from cd9600:acd0 failed with error 19.

mountroot> ?

List of GEOM managed disk devices:
   diskid/DISK-HP0C......... ada0