gkrellm2 scans for sensors in /sys/bus/i2c/devices. The better path in newer kernels would be the /sys/class/hwmon hierarchy. The attached patch adds this to gkrellm-2.2.9 and has been submitted upstream. It might still take some time until it is applied, so here it is.
Created attachment 100257 [details, diff] Patch to add Support for the /sys/class/hwmon hierarchy
I forgot to mention that the new K8 thermal sensor supoprt in the 2.6.19rc kernels is not seen in /sys/bus/i2c/devices but onlyin /sys/class/hwmon. That's why I did this patch in the first place ;)
Did you send this upstream?
Yes, I did, but didn't receive an answer until now. I'll resend it to their mailing list, but for now I'd be happy if it would be included with gentoo.
The patch was adapted into 2.2.10, just to close this bug.