GEOM loose end?

Hi

Several times now I've encountered following situation:

I have harddisk with two slices, remaining space unallocated.
There's FreeBSD system installed on the first slice, other one used
as temporary storage, i.e. both have disklabel and mounted
filesystems.
Now I want to create third slice for whatever reasons. I know that
it's impossible without setting special geom debugflag, so I'll set
it kern.geom.debugflags=16. Using sysinstall I'll create the third
slice and write new slice table down to disk. Fdisk(8) confirms that
third slice is there. The only thing missing is now /dev entry for
this slice, there's no /dev/adXs3. This /dev entry will be created
when I reboot the system, but that's not acceptable. Any workaround?

Thanks
-- 

Vallo Kallaste