mga_vid -- unresolved symbols galore

[Peter Nome <peter@cogweb.net>]

I have a graphics card that's detected by lspci as Matrox Graphics, Inc. MGA G200 
AGP (rev 03), and XFree86 finds Chipset mgag200. I got the Matrox driver components 
and the Matrox HAL module loads. My problem is that the mga_vid module from 
mga-vid-source fails to load; it builds fine but I get this on insmod:

/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol __ioremap_R9eac042a
/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol kmalloc_R93d4cfe6
/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol unregister_chrdev_Rc192d491
/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol pci_find_device_Rc584f4e3
/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol remap_page_range_R69d01e73
/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol pci_read_config_dword_R0bf170e2
/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol register_chrdev_Rfc510363
/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol sprintf_R1d26aa98
/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol kfree_R037a0cba
/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol printk_R1b7d4074
/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol simple_strtol_R0b742fd7
/lib/modules/2.4.20/misc/mga_vid.o: unresolved symbol iounmap_R5fb196d4
/lib/modules/2.4.20/misc/mga_vid.o: insmod /lib/modules/2.4.20/misc/mga_vid.o failed
/lib/modules/2.4.20/misc/mga_vid.o: insmod mga_vid failed

I'm running Debian sid with a 2.4.20 kernel and XFree86 4.2.1. I've tried XFree86 
4.3 (makes no difference) and both gcc 3.2 and 2.95 (makes no difference). What am I 
missing? Lots of people make this work -- what am I doing wrong?

Cheers,
Peter
peter at cogweb and net