Well, after about a week of compiling, I finally got a working kernel, this is my first kernel for the T-Mobile Galaxy S2 SGH-T989.
I present you, world's first OTG-enabled T-Mobile Galaxy S2!
The kernel comes with OTG USB Host mode enabled. It allows you to connect USB Flash drives, USB Hard disks (must be powered independently), USB Mouse, USB Keyboard, etc...etc..
That's about it for now since it took me a week to get a kernel working (the other ones have ended me in an infinite boot loop for a whole week, very frustrating.).
USB Enabled on SGS II Demo Video
So far the kernel only works for T-Mobile Galaxy S2 (SGH-T989) and doesn’t work yet for Telus version of Galaxy S2 but the developer might work it out in the near future. You can track down the progress of this said USB kernel on this thread here at XDA.