Hi,
you should update your Kernel and the multipath-tools. I didn't get them working stable before 2.6.13 and multipath-tools 0.4.6. If you have a look at the git you'll see that updating to 0.4.8 is worth the work.Its a RH4 AS U3 kernel (2.6.9-34) with the device-mapper-multipath 0.45.
Unfortunately christophe's wiki seems to be down, there's more info. Best regards, greetings from Darmstadt. Bernd -- dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel