My girlfriend was the web designer for the Boston Police Dept. here in Mass., for about 2 years and the policy there was that city employees did not pay ANY Social Security.
There was still money deducted from her pay, but it went into a seperately managed fund with her name on it.
When she quit the city cut her a check for $7000. There were some minor penalties for early withdrawal, but she recieved the bulk of her contributions intact.
What bothered me the most was that this was a prime example of our government exempting itself from something that it imposes on the general public.
Grrrr.. still makes me angry.