is the old airport express a1088 supported in mountain lion

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All the AirPorts work with OS X Mountain Lion. However, some old AirPort base stations don't work with AirPort Utility 6.2, so if OS X asks you to update to this version, keep AirPort Utility 5.6.1

You can install AirPort Utility 5 if you have already installed AirPort Utility 6 > http://frank.is/mountain-lion-and-the-old-airport-utility/

Thank you, thank you mende!

Frank's blog is superb, and his automator script works like a charm.

Not working for me , I am getting the Shell script error.