The ReplaceTokens filter will replace certain tokens. Tokens are
            strings enclosed in special characters. If you want to replace
                ##BCHOME## by the path to the directory set in the environment
            variable BCHOME, you could do the following:
<property environment="env" />
<filterchain>
  <replacetokens begintoken="##" endtoken="##">
    <token key="BCHOME" value="${env.BCHOME}" />
  </replacetokens>
</filterchain>
        Table E.9:  Attributes for the <replacetokens> tag 
| Name | Type | Description | Default | Required | 
|---|---|---|---|---|
begintoken | String | The string that marks the beginning of a token. | @ | No | 
endtoken | String | The string that marks the end of a token. | @ | No |