The undertaking was made last night by Treasury Minister Terry Le Sueur, who also said that pension provisons would be protected.
But Mike Budd of the telecommunications union Amicus expressed serious doubts that the Senator could give such a guarantee as a condition of sale.
He argued that there would be nothing to stop a new owner reneging on such a deal.
He told an audience of well over 100 people at a public meeting to dicusss the proposed sale that he would get the union’s legal experts to check company law to determine whether a new owner could be made to abide by such a deal.
Meanwhile, another Amicus JT representative, who sits on the pension committee, also expressed doubts about the legalities of employees of a private company being allowed to be members of a public sector pension scheme.