This may be a "Work Around" for the Galaxy S3 and Airave texting Error 97 issue. Here's what I am doing. If this quits working I will certainly update or remove this posting, however, it's been working for quite some time now.
NOTE: We were NOT in range of an airave when our phones were activated for the first time. Both phones were activated at the Sprint store.
1: UNPLUG your Airave.
2: Put all of the affected phones into Airplane mode shutting off all radios in the phones.
3: Now plug your Airave back in and let all 4 lights green up solid. (I know, this seems like it takes forever)
4: Wait 2 more minutes. (Have Patience Danielson)
5: Now and only now, take your phones out of airplane mode and give them a few minutes to sync up with the Airave. Don't dial the *99 thing either. just wait until your signal bar goes to full strength while in close range of the Airave.
6: You should now be able to send and receive text messages. (It works at my house anyway)
DO NOT UPDATE PROFILE, PRL, OR ACTIVATE A NEW PHONE WHILE IN RANGE OF AIRAVE. If you have done this, it would be a good idea to get out of range of Airave and acquire cell tower signal, and only then update your PROFILE and PRL.
NEVER ACTIVATE A NEW PHONE IN RANGE OF AN AIRAVE. If you have done this, you will probably need to contact Sprint and have them change your MSID/reactivate your phone while in cell tower range only and away from an Airave.
Here's how I came up with this: Of course I called Sprint tech support first when we noticed the issue with our brand new Galaxy s3 phones. My phone would text fine but her's wouldn't send any outgoing text messages. It kept giving her an error code 97. He tweaked some settings and reset the airave remotely. Now her phone would text but mine quite working and I was getting the error code. He said it was a known issue, and that Sprint was working with the manufacturer of the Airave on a solution. To sum up the entire conversation, he basically said to try resetting the Airave "When" it quit working and "Maybe" that would fix the problem. He confirmed that we were stuck with this issue until a software/firmware update was implemented with either the Airave or the GS3 phones. We would either have cell coverage and no text, or be forced to unplug the airave, go upstairs, and maybe get a signal to send a text or make a phone call. This simply isn't a viable option for us as our main living area is downstairs and we don't get any reception there.
Well, the texting issue bent back and forth between my S3, her S3, and most of the time both S3 phones not sending outgoing texts (code 97). It never once affected the other 2 LG rumor phones in the house and they worked flawlessly. Apparently this issue only affects certain phones and the GS3 is one of them. Simply resetting the Airave was just not doing the trick. Rarely (actually never) did just unplugging or resetting the Airave work on both phones at the same time. It finally dawned on me one day that when her phone would text and mine wouldn't, that she was out of the house when I reset the airave. Her phone would now text and mine wouldn't, Then we had a short power outage at the house another day. I was not home but she was, Then only my phone would text and hers quit working. So a thought popped into my head to run a little experiment and try taking the phones out of service while rebooting the airave. So far so good. Both phones are working 100% of the time unless we have a power blip or the Airave resets while we are in range. Apparently this is an issue that only happens with certain phones, and the Galaxy S3 is one of them. When the Airave resets in range of Galaxy S3 phones, there must be some sort of "handshake" routine that runs during initialization. I believe that this may be the source of the issue. Putting the phones in airplane mode stops this from happening when the Airave goes through the boot sequence and finally acquires "mobile".
I ran further experiments rebooting the airave with the phones radios turned on to see if the problem returned. The problem returned upon the first boot and only 1 phone could send outgoing texts. Further experiments proved (at my house at least) that having the radios turned off while booting the Airave solved the problem. Testing back and forth, and sure enough, when the radios were turned off (airplane mode) both phones worked fine. When the radios were turned on, the problem returned. Anyway, it is working at my home at least, and I can only hope it helps others out there to get around this very frustrating problem.
I love Sprint and my Galaxy S3 phone, I love the fact that they provided me with a free Airave to fix a reception problem, but the Texting bug is a pain in the rear irregardless. I certainly hope they are able to resolve this issue soon.
Good luck and I hope this helps others with this frustrating problem until a permanent solution is found.