Wellbutrin and Methadone interaction?

[Gentlemansyd]

I was prescribed Wellbutrin (buproprion) for smoking cessation and have been on it for roughly 3 weeks.  It is the SR, 150mg in the AM and 150mg in the PM.  I have also been on methadone for roughly five years and have been at the same dosage of 25mgs for over a year.
Once starting buproprion (i got the generic), the side affects were pretty bad.  I felt like I was on amphetamines. Slowly that side affect wore away but within the past 4 days, I have been waking up in the middle of the night feeling like I am going into withdrawals with either restless legs or arms, one or the other and not both, that feel VERY uncomfortable like my skin is crawling.  On top of that, if I wake up at all after going to bed, I cant get back to bed.  
Could the Wellbutrin be affecting my body's methadone uptake?  Keep in mind that this problem has just started roughly 20-25 days into treatment.  On top of that, it hasnt done anything to quell my smoking.