Three staff at a third-level college received €627,000 in salary payments between them - despite having no clear role.
The staff did not have any defined duties following the amalgamation of the Tipperary Institute into Limerick Institute of Technology (LIT) in September 2011, according to Comptroller and Auditor General Seamus McCarthy.
Mr McCarthy told TDs the staff were deemed surplus to requirements, but were not laid off and remained employed by LIT.
"The cost for those staff to date has been €627,000, of which €216,000 was incurred in the year ended August 31, 2014," he told a session of the Dáil's Public Accounts Committee (PAC).
"They have an approved level of staffing and these are above that level. In this case they have no work. They are obviously doing something but they have no formal assignment in the institute."
One committee member, Independent TD Shane Ross, described the disclosure as "crackers" and "bananas".
Another PAC member, Fine Gael TD Patrick O'Donovan, said the people involved would have earned an average of €72,000 a year and queried whether anything had been done about the situation.
The matter came to light when the institute's accounts for 2014 were laid before the Oireachtas.
The C&AG said he didn't know what the staff were doing now and said he had to be careful not to identify them.
Mr McCarthy said: "I think it is relatively unusual. It does happen where organisations are amalgamated that people become surplus to requirements. Generally then what happens is they would be transferred to other organisations that can use their skills." The Irish Independent understands that while there was a period where the staff had no defined duties, this has since been resolved.
In a statement LIT said: "Arising from the integration of Tipperary Institute into LIT, a five-year integration process for redeployment of staff was immediately undertaken and is completed as of the start of the current academic year, 12 months ahead of schedule."