relief work - can i claim social welfare

My wife is a guidance counseller in a VEC secondary school. She is employed on a temporary basis which means she is not paid for holidays (xmass, easter, summer). Because of this she has a second job whereby she is on the books as a relief worker. Usually she will get shifts during the summer but very occasionally she will get some weekend work during the rest of the year. The VEC have advised her to sign on during this xmass time. She does not expect to get shifts in the 2nd job during this time. Is it possible to sign on whilst still technically employed in another job?

thanks

Yes, school workers do it all the time. They get paid for the days where holiday pay has not accrued.