device-mapper library

I apologize if this is the wrong place to ask this; kindly direct
me to the appropriate place if so.

Is there an issue building device-mapper.1.00.1[89] against
2.6 kernels?  struct dm_target_msg does not appear in the
kernel headers for 2.6.5 or 2.6.7 (include/linux/dm-ioctl.h)
but does appear in kernel/ioctl/dm-ioctl.h in the device-mapper
sources.  Is there a set of 2.6.x patches somewhere I missed?

Thanks!

-Bob