[Samba] Can't validate USER@DOMAIN in Runas

[Linda W]

I have my XP-Pro machine setup as a member of an Samba-based Domain server.

I usually run as "linda@<localmachine>", but wanted to try running a
program using "RunAs" in the "Home", DOMAIN my machine belongs to.  The
runas command says:
RUNAS [ [/noprofile | /profile] [/env] [/netonly] ]
        /user:<UserName> program
with Notes:
NOTE:  Enter user's password only when prompted.
NOTE:  USER at DOMAIN is not compatible with /netonly.
NOTE:  /profile is not compatible with /netonly.
and Examples as:
 > runas /noprofile /user:mymachine\administrator cmd
 > runas /profile /env /user:mydomain\admin "mmc %windir%\system32\dsa.msc"
 > runas /env /user:user at domain.microsoft.com "notepad \"my file.txt\""

The output on my XP machine is:
 > runas /user:linda at Home bash.exe
Enter the password for linda at Home:
Attempting to start bash.exe as user "linda at Home" ...
RUNAS ERROR: Unable to run - bash.exe
1326: Logon failure: unknown user name or bad password.
---
    I verified on my "Samba" server (running SuSE 9.1)
to have the following in my "/etc/samba/smbpasswd" file:

linda:1000:08...<long hex string>...:8...<guid looking thing>...B: \
[        ]:LCT-4<##>E:

I ran smbpasswd on the server to verify I'd set the correct password,
and "linda" is in the "Domain Users" and the "Domain Admins" group.

Is there something I am missing in how I'm supposed to do this?  It's
the first time trying "runas".  The XP machine "knows" it's part of
the "Home" domain.  The Domain server is setup as a logon server.
Since it is my first time trying this it's likely some config problem
"somewhere".  Any clues?  Has anyone done this that might have
some tips?

Thanks,
Linda