Topic: could not mount any secondary drive partitions

[winsti]

Hi,
I just successfully  installed SME 7.0 on a machine with two identical PATA HDs on the primary interface.   I have a  disk from a previous sme 6.5 installation from which I wish to copy a number of folders.  I installed this HD on the secondary controller and could see hdc1, hdc2, hdc3 but I couldn't mount these partitions anywhere.  I always got the message
mount: /dev/hdcn already mounted or /mnt/mountpoint/ busy

I found this Link:

http://lists.centos.org/pipermail/centos/2006-February/060993.html

where the top suggestion
>>I've added this to rc.local in the interim
>>
>>dmsetup remove_all; sleep 10; mount /dev/hde1
>>
allows me to mount the partitions and copy my data over.

Why is this necessary?  Is it a bug in LVM as some posts suggest or have I just not found the magic command to mount just another drive to SME 7.0?
I haven't tried removing the statement from rc.local yet and so I don't know the full consequences of my actions.  I will report on these later