Too many active children of 'whole'

Hi:

Using FreeBSD 8.x snapshot 200902, On a 160GB SATA HDD, 
i tried creating a 25GB slice and then selected 
'install a standard MBR (no boot manager)',
the installer gave a warning as:

"Disk Slicing warning:
 Too many active children of 'whole'"

What exactly does this mean ?


thanks
Saifi.