Menu Extras and MCX
There’s a little quirk when you’re controlling menu extras for Mac OS X client systems using MCX. Well, there’s more than one quirk, but you know what I mean.
By default, new users of Mac OS X systems get Blutooth, Time Machine and Volume menu extras, as well as the clock. The Spotlight control is separate, so we won’t mention it here. On our systems I don’t really want to display the Bluetooth menu extra, we don’t use Time Machine and the volume is controlled by the external audio interfaces, so they could all do with going away.

Digging through ~/Library/Preferences/ByHost shows that this is handled by a configuration file called com.apple.systemuiserver.XXXX.plist and as such you can control what appears using the configuration options in Workgroup Manager. The key you’re after is sensibly named dontAutoLoad, which can contain the paths to any Menu Extras.
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