Forgot to mention that the architecture is x84_64, and I used gcc 4.0.1

Is it related to something I should compile in the kernel?

For some reason (maybe my mistake) the original bug didn't arrive to dri-devel ml. 
I attach it below:





I compiled cvs drm on kernel 2.6.13-mm1. This is the output of modprobe:
# modprobe radeon
WARNING: Error inserting drm
(/lib/modules/2.6.13-mm1/kernel/drivers/char/drm/drm.ko): Unknown symbol in
module, or unknown parameter (see dmesg)
FATAL: Error inserting radeon
(/lib/modules/2.6.13-mm1/kernel/drivers/char/drm/radeon.ko): Unknown symbol in
module, or unknown parameter (see dmesg)

and dmesg says:

drm: Unknown symbol pci_pretty_name
radeon: Unknown symbol drm_open
radeon: Unknown symbol drm_fasync
radeon: Unknown symbol drm_poll
radeon: Unknown symbol drm_get_resource_len
radeon: Unknown symbol drm_core_get_reg_ofs
radeon: Unknown symbol drm_irq_uninstall
radeon: Unknown symbol drm_get_dev
radeon: Unknown symbol drm_ioctl
radeon: Unknown symbol drm_exit
radeon: Unknown symbol drm_debug
radeon: Unknown symbol drm_core_get_map_ofs
radeon: Unknown symbol drm_init
radeon: Unknown symbol drm_addmap
radeon: Unknown symbol drm_get_resource_start
radeon: Unknown symbol drm_vbl_send_signals
radeon: Unknown symbol drm_cleanup_pci
radeon: Unknown symbol drm_ati_pcigart_init
radeon: Unknown symbol drm_mmap
radeon: Unknown symbol drm_order
radeon: Unknown symbol drm_ati_pcigart_cleanup
radeon: Unknown symbol drm_compat_ioctl
radeon: Unknown symbol drm_core_reclaim_buffers
radeon: Unknown symbol drm_release

On linux-2.6.13-mm1, the pci_pretty_name() macro has been removed. The following:

sed -e 's|pci_pretty_name(dev->pdev)|\"\"|' -i linux-core/drm_stub.c

solves the problem.

The use of pci_pretty_name appears to have been fixed (via code in
linux-core/drm_compat.h) on September 17th, 2005.