dumping on RAIDframe

[Edgar Fuß <ef%math.uni-bonn.de@localhost>]

Didn't RAIDframe recently (for certain values of "recently") gain the function 
to dump on a level 1 set? Should this work in -8?
swapctl -z says "dump device is raid0b" (and raid0 is a level 1 RAID), but 
reboot 0x100 in DDB says
dumping to dev 18,1 (offset=1090767, size=8252262):

dump device not ready

What am I missing?

The offset (as reported by disklabel) of raid0b within raid0 is 2097152 (1G), 
the partition size is 67108864 (32G), so maybe something's wrong with the 
offset and size values (whatever unit they are in) DDB reports.