Northern Ireland Civil Service Address

Hey all;

My mum is looking for a new job and is looking to apply for the NI Civil Service; She was born in the north ,she has an Irish passport etc; but on the fist page it asks for an address. She lives in the Republuc now but also has an address in the North; it would be more convenient if all mail etc would be sent to the Republic but she is worried if she applies for a job up North they would put people that have a southern address at a disadvantage!

Has anyone any experience? Do they care about the address for purposes of the job or is it solely to contact people?

Thanks