Time & Date Setting Error

Hi mates,
I downloaded and installed Linux Mint 9.0 XFCE.
While changing the time and date in "Time and Date Settings," I clicked on the "hour" arrow, I got an error message that read:

Error:
The configuration could not be saved.
An unknown error occurred.
Please advice as to what should I do, in order to sort out this error.
Thanks in advance.
