The Monetary Authority of Singapore (MAS) made an error in the newly launched SG50 commemorative notes sets by misspelling the name of Singapore's first President, Mr Yusof Ishak, on the packaging.
It is spelt on the cover fold and enclosed booklet as "Yusok Ishak".
A blurb explaining the design of the special $50 note reads: "The front design features Mr Yusok Ishak, our first President".
The late President's portrait is on both the $50 and $10 commemorative notes.
The notes, which were launched yesterday, do not contain errors.
Mr Ravi Menon, managing director of MAS, which issued the sets, said last night he took full responsibility for the spelling mistake.
"This should never have happened, (it) is not acceptable, and I take full responsibility. I apologise on behalf of my colleagues who worked hard to prepare the notes and folders but are deeply disappointed that we made this most unfortunate mistake. We will put this right," he said.
A spokesman for the MAS said it is now printing stickers to replace the misspelt part of Mr Yusof Ishak's name. They will be affixed to the folders from Tuesday.
Those who have already exchanged their old notes for the new ones may also obtain the same stickers for their folders from nine banks, including DBS Bank/POSB, Oversea-Chinese Banking Corporation and United Overseas Bank.
But Mr Jason Teng, 37, who obtained 15 sets yesterday, was not bothered by the error.
"I wouldn't have noticed it if it wasn't pointed out to me. I care more about the note than the packaging," said the jeweller.
He added candidly: "The error might even turn the commemorative set into an even more rare collector's item."