I have never heard of that sleep disorder before but I will be sure to ask my psych & my Dr.s & see if they have.
Like leahcim said I have been told I have done many not so strange & strange things while on my medications, remembered & not. I once got a call from my daughter asking me to babysit my grandkids, agreed got up drove over babysat drove home woke up & didn't even know that i had done it
I also have been diagnosed w/ bipolar, severe sleep disorder etc. & one of the meds I take is Ambien so it could very well be the lunesta.
Talk to your Dr.s about switching meds or verifying this new sleep disorder & finding a better solution for it!
We all react differently to meds so I would definately consider along w/your Drs. opinions on trying a different med.
Good thoughts for good sleep & health your way.