He appealed to the media not to get “their knickers in a twist” over a comment about “remembering the Black and Tans”.
It was written into page three of the book, which is in Limerick City Hall and is already full of signatures.
“It is a non-story. More than 1,000 people have signed the book and there are some very moving comments.
“You will always get something silly written by some socially inadequate person and in Limerick people are inclined to fly off the handle when some small thing like this happens,” Mr Scully said.
“The spire in Dublin is cleaned three times a day to remove graffiti and there is nothing in the media about it,” he said.
Mr Scully said the Black and Tan comment will be erased before the book is sent to London.
“In a situation like this it is impossible not to get somebody putting in something negative. People do this for attention which they do not deserve.”
He said the person responsible had turned back to page three of the book hoping their contribution would not be noticed.
“Down the years I have been involved in the collection of many petitions and you will always get at least one or more crank comments written in. It’s nothing new,” Mr Scully said.
He revealed that he received a letter from the Mayor of London, Ken Livingstone, thanking him for opening the book of condolence.
“Mayor Livingstone wrote a very kind letter thanking the people of Limerick for this gesture of opening a book of condolence and he referred to the strong links his city has with the people of this country,” Mr Scully said.
He said the book will remain open at the City Hall until next Friday.
Cllr Jim Long said the crank comment was a scandalous act.
“It is an absolute disgrace that someone would even think of doing this, let alone carry it out. I condemn it in its entirety,” he said.
When the book of condolence is completed, said Mr Long, it would be forwarded to the Mayor of London’s office.