I saw this hint in the mailinglist lately.
Thanks to the original author
EnablePlainTextPW:
The location of this key in the registry has changed from NT4 to Win2000.
The new way of setting this is:
Key:
HKLM\system\currentcontrolset\services\LanmanWorkStation\para
meters
name: EnablePlainTextPassword
Data type: REG_DWORD
Data: 1
(binary)
Reboot required to take effect.