I spent over an hour on the help line with the local telecom operator. We could not get the Huawei E3276 USB modem to work on MAC OS X 10.8.4 on a Macbook Air 2013.
It works without any problems on lower versions, e.g. MAC OS X 10.7.5, on a Macbook Pro but not with 10.8.4 on the Macbook Air where the modem is shown as connected (also under network preferences), however, it does not appear as an available network in the drop down list of the netwok utility.
The telecom operator can see it as connected and exchange SMS#s, but for some reason neither Safari nor Mail can "see" the modem.
Any workaround or fixes by either Apple or Huawei are appreciated!