T9 external bluetooth keypad for iphone

i'm starting a new project for my own pleasure, it's a small t9 keypad (like the old nokia one ) to use on the iphone via bluetooth. ( i may use the capacitive keypad from sparkfun for the interface ).
So i can text or take note one handed. So heres my problem so far :
I know i ll have to use a HID bluetooth module like the RN-42 so the device could be recognized as a keyboard. But the main problem is that iphone doesn't support t9 natively. So i was thinking about making a t9 to text converter via mcu on the keypard to send the correct values to the iphone as a "normal keyboard". I mean for example if i want to type "hello" on a t9 pas i should to tap 4 two times for the h, two time 2 for the e, etc... so i need a program that do the conversion, two times 4 tap = h, send keycode "h" to iphone.
My main question basically, is this possible, and am i on the right track ? and then is there any arduino t9/keyboard library that i should look into ?

Best regards
Jeremie

Using the HID-based bluetooth module is crucial (and is often a key most people miss.)

"and then is there any arduino t9/keyboard library that i should look into"

Never heard of such a library and Google doesn't seem to suggest there is one either.

Wikipedia says the technology has a patent, so the algorithm should be easy to find.

You can download t9 keyboard apps for the iPhone, although I only ever use one thumb for typing and can match my regular keyboard speed.

I thought t9 was a predictive algorithm, so rather than 4433555555666 for 'hello', you just enter 43556, and a dictionary lookup finds 'hello'.

yeah in fact reading the t9 page on wikipedia, i m more interested in a multi tap technology Multi-tap - Wikipedia

As for the t9 app on the iphone the whole project is to not have to buy or download an exterior app, and doing all the conversion on the keyboard itself, so it could work with any bluetooth equiped phone, anytime.

The t9 should require a small lcd on the keyboard so i can validate each word...feasible but not in the first prototype.
I m just gathering infos from all your great minds right now :wink:

i ve found this...Google Code Archive - Long-term storage for Google Code Project Hosting. maybe a start !