When the guest is in text mode only the first line is shown.
Tested under KDE4 + NVidia binary drivers + Linux 2.6.31-gentoo-r1 (x86-64) using QEMU 0.12.2.
Attached example:
<<inline: 2.png>>
It should be like (took in Mac OS X 10.6.2 using QEMU 0.12.2):
<<inline: 4.png>>