Defining format for Property

We have a task in ANT to update propertyfile with format like

<propertyfile file=.....>
  <Entry key=proper.name
            pattern=......
  </entry>
</propertyfile>

And this can change the pattern in property file, now I do not want to change/update property file but still I want that, if the value of key is 1 lets say proper.name=1 then my target should read it as "01" and NOT "1".

Now can I do that without updating the propertyfile ?

THanks