Mr Mountain, who started working for Humberside County Council in 1976, was seconded to the advisory service in 1991. For two years, his job as head of science and technology at a Hull secondary school was kept open for him.
In 1993, he was appointed as a curriculum support teacher for a two-year period and resigned from the school - but not from the authority. His new contract contained a clause waiving his rights to make a redundancy or unfair dismissal claim. But Mr Mountain says it was not made clear to him that this clause applied to the rights he had built up during 15 years in the classroom, as well as the two years of his fixed-term contract.
Mr Mountain then accepted another two-year appointment with Humberside. Again, his contract contained a waiver clause but, confusingly, it also said that for the purpose of redundancy payments his continuous service would be counted from the time he first joined the authority on January 1, 1976.
When this second contract came to an end there was no further work for Mr Mountain with the authority, which told him he was not entitled to any redundancy pay. Although his union, the National Union of Teachers, agreed that the authority was acting within its rights and had no case to answer, Mr Mountain decided to take his claim to an industrial tribunal.
The tribunal found in his favour, saying that the waiver clauses applied to the two fixed-term contracts and not to the "continuing and underlying contract of employment" that he had had since 1976. The tribunal ordered the authority to pay Mr Mountain pound;4,935.
This decision was later overturned by the Employment Appeal Tribunal, which held that Mr Mountain had "unwittingly, quite probably" waived all his rights to redundancy pay. Recognising that the law had produced a "particularly harsh result" in this case, the judge recommended that the authority should make "some ex-gratia acknowledgement of all those years of service". The authority duly sent him a cheque, without enclosing so much as a compliments slip.
Mr Mountain, who now works for another authority, is unlikely to be the last teacher to have to fight for redundancy pay. Although the Employment Relations Bill proposes to ban employers from making people on fixed-term contracts sign away their rights to claim unfair dismissal, waiver clauses will still be permitted for redundancy payments.