I can only suggest you cancel the text package and add data package. Then use google voice as your texting number. It will be free as google voice uses only data and you have unlimited data. Only drawback I see is that you will have two separate number for people to remember. One for text and one for voice. Shouldn't be a problem if you mass text everyone your new texting number.Edit
I just saw your profile that you are using intensity. The above only works if you're using a smartphone. Do Not get an unlimited data plan with an Intensity.