If I say 'Keep configuration', it says that the following hardware has been
added:

Matrox|MGA G400 AGP

Wasn't that what it thought had been removed?

This also happens with kudzu-0.24-1.

If you go along with kudzu, and tell it to unconfigure and configure when it
tells you to, the following change to hwconf is made:

--- /home/twaugh/hwconf Tue Jan 25 15:39:34 2000
+++ /etc/sysconfig/hwconf       Tue Jan 25 15:41:52 2000
@@ -62,6 +62,15 @@
 deviceId: 1229
 pciType: 1
 -
+class: VIDEO
+bus: PCI
+detached: 0
+driver: Card:Matrox Millennium G400 16MB
+desc: "Matrox|MGA G400 AGP"
+vendorId: 102b
+deviceId: 0525
+pciType: 1
+-
 class: MOUSE
 bus: PSAUX
 detached: 0
@@ -84,12 +93,3 @@
 desc: "Maxtor 90680U3"
 physical: 14112/15/63
 logical: 830/255/63
--
-class: VIDEO
-bus: PCI
-detached: 0
-driver: Server:SVGA
-desc: "Matrox|MGA G400 AGP"
-vendorId: 102b
-deviceId: 0525
-pciType: 0

Oh, yuck; the driver setting changed, so it thinks
the device needs reconfigured. This is going to
be messy.

Fixed in kudzu-0.25-1.