I recently moved my data only mobile plan from 3 to Optus due to their support of fallback to GPRS at no additional charge (ie better coverage).

Optus Roamer USB ModemWith this came the Optus Roamer USB modem, which is actually a Huawei E220 modem in a “nice” Optus white and yellow case.

The problem was I wanted to run this on both my PC and my Mac, and Optus don’t support Mac OSX. The good thing is, Huawei do, and drivers are available (but hard to find).

Here’s what you do (new instructions - old ones below):
1. Unplug the modem (if you have it plugged in).
2. Download the Mobile Connect for Mac OSX below.
3. Run “Mobile_Connect_Drv_App.pkg” and follow the instructions.
4. Now plug in your modem.
5. Open System Preferences, then Network.
6. If running Leopard (10.5.x), click on the “+” and from the Interface drop-down choose “HUAWEI Mobile”, otherwise under Tiger (10.4.x) set “Show” to “Network Port Configurations” and choose “New”, then name it and select “HUAWEI Mobile” from the port drop-down.
7. Name it whatever you want (I called my Optus Wireless), and click “Create” (or OK under Tiger).
8. Select your newly created connection and place *99# in the Telephone Number.
9. Click on “Advanced”.
10. Under modem, choose Vendor “Other”, and then choose the HUAWEI 3G Modem (could be named differently - but will say Huawei) as the Model.
11. Click OK, then click on Connect to test your connection.

Optional Step: If you want to try a program made to give you more info and monitor your E220 on Mac OSX, try CheetahWatch, although I haven’t had much luck getting it to work which with some quick help from the developer I got working (looks like it was a corrupted download). 

Alternate Instructions - Use only if the above doesn’t work:
1. Unplug the modem (if you have it plugged in).
2. Download the Mac drivers below.
3. Run “HuaweiDataCardDriver(2.6)-intel.pkg” and follow the instructions.
4. Once done, run “Huawei_DataCard_Drv_App_Intel.pkg”, again following instructions.
5. Follow the above instructions from step 4.

For “3″ Users, Evan has a great guide (with nice easy to follow graphics) here.

Regards,
Shane.

Download:
Download Huawei E220 Mobile Connect for Mac OSX:
Huawei E220 Mac OSX Mobile Connect (2380) - 893.08 KB

Optional:
Download Huawei E220 - Mac OSX Intel Drivers *
Huawei E220 Mac OSX Intel Drivers (9253) - 98.38 KB
* Try this if method above does not work

Optional:
Download Huawei E220 - Mac OSX PowerPC Drivers *
Huawei E220 Mac OSX PPC Drivers (2067) - 75.23 KB
* Try this if method above does not work