Help USB OTG Issue

[twadebarcelona]

HiI have a Samsung Galaxy S and a couple of weeks ago i rooted it to use usb otg features as I had just received a usb otg cable from Amazon. The process went well but when i connect my 16gb usb flash drive to the otg cable then attach the otg cable to my phone nothing happens. Am I doing something wrong as the rasin i wated to do it was so that it would be a cheaper alternative to buying a new micro sd card and I wanted to be able to access other files when im out. What do I do to get it to read my usb flash drive.