Winlogon - cannot set empty password from ruby

Hello

I tried to make a ruby script that makes Windows XP automatically log
on the local user “user” on startup. The purpose of the script is to
find out the computer name and put it into the winlogon registry along
with the username and password.

However, I cannot set the password to an empty string. It appears
empty but when I restart Windows it says the logon failed, and there
is a dot in the password field.

When I import the empty password using a registry file it looks the
same but it works. I wonder if I do something wrong when writing the
registry, there is also a parameter for length. The computer name is
set correctly, though. Otherwise it won’t work even with the registry
file.

I am using some older ruby one click installer (the version in the dll
is 1.8.5.0 2006-08-25).

Attaching the hack for reference. I would appreciate ideas how to make
it work with the script only.

Thanks

Michal