Disable Administrator account on Windows 7 Starter Edition

How can I disable the Administrator account on Windows 7 Starter Edition? I enabled it using the NT Password and Registry Editor so that I could install software for a client who didn't leave me their netbook password. There doesn't appear to be a way to disable it using Windows itself (no lusrmgr.msc, net user Administrator /enable:no gives an error, no secpol.msc).

I solved this by loading the SAM registry hive and editing the Domains\Account\Users\000001F4\F value and setting the 38th byte to 11. 11 is disabled 10 is enabled.

I used the NT Password and Offline Registry Editor http://pogostick.net/~pnh/ntpasswd/regedit.txt to do this. Once you cd to the right key, the commands to edit are as follows:

ed 000001F4
d      <to print>
:38    <enter 11>
d      <to print>
s
quit