Solicitor and property developer Michael Lynn will be cross-examined for two days in the High Court next month over six properties in his files.
The cross examination is part of the disciplinary proceedings being taken against him by the Law Society.
The court was told today that Mr Lynn is ill at the moment.
Any testimony given by him in the Law Society's proceedings cannot be used against him in any criminal proceedings.
Mr Lynn's practice was closed last month and his accounts have been frozen. A Law Society investigation uncovered 'acts of dishonesty' in relation to clients' money.
It has also emerged that he had multiple mortgages with various financial institutions on foot of undertakings on security that have not been honoured.
Separately, the High Court will hear the case being taken by Irish Nationwide homeloans manager Barry Fitzgibbon against his employer tomorrow.
Mr Fitzgibbon says he is being scapegoated for more than €20m in loans given to solicitors Thomas Byrne and Michael Lynn because of previous difficulties in his employment.
He also claims that at least one substantial loan to Michael Lynn - a €4.1m loan for a house in Howth, Co Dublin - was directly approved by the managing director of Irish Nationwide, Michael Fingleton.
He says that he turned down a loan application by Thomas Byrne in April because he had suspicions that something was not right but the loan was later allowed to proceed by Michael Fingleton after an appeal by the branch manager.
Irish Nationwide will get a chance to put forward its side of the case tomorrow.
