I'm thinking to leave OVI way: too many interrogative, too many problems...
I'm consider two alternative road now:
A- Give it FOSS and wait for donations.
B- Again FOSS but with something a bit annoying (a pop-up that appears every x times or something in text field) removibile entering a code. This way have IMO bad and good point: good ones are that you can test it and choose if and when donate. Bad is that implementing a such things requires too much time (and again I prefer use my time for add features) and there is a cost for maintein a little server for code authentication. In addition this way add "brainy" things that I dislike.
And perhaps someone can fork fastsms to remove the "protection" (ugly word)

@ysss: As I said before code will be available first or after. I can add that if MohammedAG, people that helped me or others well-knowed developer need the code asap, I can give source-code when it will be ready.