Comment 1 for bug 54202

similar configuration: Kt266 motherboard, ATI Technologies Inc Radeon RV200 QW [Radeon 7500] graphics card, using Ubuntu Feisty with all the updates. I can confirm that this bug is present with Xorg 7.2.0 and kernel 2.6.20-16-386. Same error is reported by km:
[263532.480000] km: probing 0000:01:00.0
[263532.480000] km: using irq 11
[263532.480000] Register aperture is 0xe1000000 0x00010000
[263532.480000] kms variables: reg_aperture=0xf8f60000
[263532.480000] km: DMA_GUI_STATUS=0x00000002 entries=2
[263532.484000] sizeof(kmfl_template)=780 sizeof(KM_FIELD)=52
[263532.484000] Device 0000:01:00.0 (0x1002:0x5157) corresponds to /dev/video0
[263532.484000] kms variables: reg_aperture=f8f60000
[263602.872000] Processing "VIDEO_STREAM_ACTIVE"="1" int_value=1
[263602.872000] Purging transfer queue
[263602.872000] WARNING ! Radeon memory controller is misconfigured, disabling capture
[263602.872000] WARNING ! upgrade your Xserver and DRM driver
[263602.872000] km: no data is available until AVview or xawtv is started