Anybody experiencing symptoms withdrawing from Tramadol (Ultram)?

I have taken it for back pains and yes, it can be addictive. I have researched it on the internet and found several ppl either say it never helped them or it helped them so much that they became very addicted to it. It doesn't seem like too many dr.'s actually prescribe this drug or know very much about it. I've never had any issues with it, but I haven't taken it for such a long period of time.