Hello! I believe if your "PLAN" includes free unlimited texting and picture messaging then you should not be charged. The data use should be getting covered via the PLAN regardless of the presence of the data plan.
You're very welcome. The other reason you should not have to worry is the fact that your device (although a smartphone) does NOT require a data plan because it was released in 2007. Verizon's policy states that any smart phone released prior to 11/2008 can be activated with Verizon even now without the now required data plan. So again, so long as you have a basic plan that covers texting or picture messaging or the supplemental package that does then you should NOT be incuring charges for the use of those features
I also have the i760 and don't have a data plan. Instead, I'm on the pay-as-you-go plan. I have unlimited text, picture, and video.
Every time I've send a photo, some small amount of data charges are posted to my account. When I've inquired in the past, I was told it was the nature of the PDA to incur these charges, because the photos are treated as data, and they are not handled in the same way as with photos on my kids' phones.
The same was true with my old Palm Treo 600.
Well there we have the other side of the coin. While a pre 11/2008 data phone can be activated now without a data plan . . . the price you'll pay for transfering ANY data without the plan in place will indeed be a steep price if you do so with any regularity. So while you CAN activate a smartphone that is pre 11/2008 without a data plan . . . if you are going to be engaging in data transfer you really should reconsider the presence of a data plan to cover those charges folks.