sftp cd to root directory not working

[Gary Richards]

Hi,

I've recently been trying to script up downloading some files from an 
sftp server, but am seeing some very strange differences between using 
lftp and using sftp. I wonder if someone can see what i'm doing wrongly 
with lftp. Example below:

[r...@abcd ~]# sftp -o "IdentityFile=/home/send/sshprivatekey" 
usern...@x.x.x.x
Connecting to x.x.x.x...
sftp> ls
HomeDirA  HomeDirB
sftp> cd /
sftp> ls
RootDirA RootDirB

The above works as expected, in my home directory I see some 
directories. If I cd /, then ls again, I see some directories in the 
root directory. However, when I do this with lftp I get this:

[r...@abcd ~]# lftp
lftp :~> set net:max-retries 1
lftp :~> set sftp:connect-program ssh -i /home/send/sshprivatekey
lftp :~> open -u username, sftp://x.x.x.x
lftp usern...@x.x.x.x:~> ls
drwxrwxrwx                      0 2002-06-24 08:50 .
drwxrwxrwx                      0 2002-06-24 08:50 ..
drwxrwxrwx                      0 2009-11-10 03:21 HomeDirA
drwxrwxrwx                      0 2008-09-09 13:32 HomeDirB
lftp usern...@x.x.x.x:~> cd /
cd ok, cwd=/
lftp usern...@x.x.x.x:/> ls
drwxrwxrwx                      0 2002-06-24 08:50 .
drwxrwxrwx                      0 2002-06-24 08:50 ..
drwxrwxrwx                      0 2009-11-10 03:21 HomeDirA
drwxrwxrwx                      0 2008-09-09 13:32 HomeDirB

As far as I can tell, the cd / worked ok, but when I ls, I get a list of 
the contents of my home directory again?! I can't see anything obvious 
that i'm doing wrong.

Unfortunately I have no idea what ssh/sftp server runs at the other end 
and I don't think it would be easy to find out (unless there's some 
magic I can perform with sftp?).

If it's helpful, this is lftp 3.7.11, on RHEL 5.4.

Thanks

Gary