iso entities (newbies question)

Hi,

My xml file is produced in single line, so i use the following command to pretty print.

tidy -xml input.xml > output.xml

But the enities in my input.xml file are also getting changed.

e.g.
input.xml => output.xml
  =>  
( => (
) => )

Please let me know how to retain my original entities ( ) and  

Thanks in advance.

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