Madaley
I have found another option you may wish to try. Its not Access Connections but it works. Its called Vodafone Mobile Broadband. After a bit of tweaking (less than 10 minutes) I got my Cell C sim running on this Vodafone software and viewing SMSs. I see that it should support SMS for your Sierra Wireless card. Only testing will prove this for sure or not.
It shows in this PDF Readme on page 7 that the device is supported: http://bit.ly/9xjlJn
You can grab the app here: http://www.softpedia.com/dyn-postdownload.php?p=67199&t=4&i=1
Instructions:
Install the software simply using all the defaults. You can choose any connection in the dropdown list. It doesn't matter as you will be changing this later and you just need something there to complete the installation.
When you run the application it will say your sim card is not recognised. It doesnt matter. Close the application.
Go to the install directory: C:\Program Files\Vodafone\Vodafone Mobile Broadband\Opco
You will see loads of network settings. Scroll down and you will find "26202 Germany". Copy it and name it "26207 Germany". Go into your new 26207 directory and rename everything you see as 26202 to 26207. I changed my settings under Prepay as well. I figured it can't hurt.
You then need to go into the XML files and change all the 26202s to 26207. Very important is the 26207.XML. At the same time change all the Vodafone.de entries to O2.
Once you are sure you have renamed and reconfigured all the files, go back to the root of Opco where all the network settings are and scroll to the bottom. You will see another file Opcos.XML. Edit that file. Scroll down and find the 26202 Germany entry. Copy that entry and paste it beneath it. Make sure its alignment is correct and the same as the others. Edit the 26202 to 26207 and rename the Vodafone entries to O2
Save the files and reopen the application. It should now prompt you that your selected network is not available but would you like to use the settings for your installed O2 sim card. Select yes. This should then show your network and offer you the option to Connect. At this time my SMS messages popped up and offered me the chance to Delete or Reply or open the SMS application. You should now also be able to open SMSs on your desktop shortcut as well as the small SMS link on the open application and in the system tray icon.
You should still be able to keep your connection through Lenovo Access Connections and just check your SMSs through the Vodafone app.
Please let me know how this works for you or if you continue to have trouble with this. I really hope this helps you.
Cheers
Hoox