You can use the same trick as with cruise control (which actually originated from the hudson website)
java -DJENKINS_HOME=C:\Jenkins -jar C:\Jenkins\jenkins.war |
java -DJENKINS_HOME=C:\Jenkins -jar C:\Jenkins\jenkins.war
HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\AutoAdminLogon=1
HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\DefaultUserName=testuser
HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\DefaultPassword=secret |
HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\AutoAdminLogon=1
HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\DefaultUserName=testuser
HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\DefaultPassword=secret