Gradle Replace text in jsp using filter

I have a jsp that contains a css link that looks like

<link type="text/css" href="/css/login-min.css" rel="stylesheet" />

In order to keep browsers from caching the css file we replace login-min.css with the name of the css and a timestamp or version number

login-min.css?t=432432423423...

In ant I would do something like

<tstamp>
  <format property="current.time" pattern="MMddyyyyhhmmssaa" offset="-5" unit="hour" />
</tstamp>

<replace dir="${deploy.path}/${name}/WEB-INF/jsp" value="login-min.css?t=${current.time}">
  <include name="includes/login_css_include.jsp" />
  <replacetoken>login-min.css</replacetoken>
</replace>

For gradle I've updated the jsp page to look like

<link type="text/css" href="/css/@loginCSS@" rel="stylesheet" />

and in the build.gradle am doing

import org.apache.tools.ant.filters.ReplaceTokens
war {
  webInf {
    from ("${webAppDir}/WEB-INF/jsp") {
      include: "/includes/login_css_include.jsp"
      filter(ReplaceTokens, tokens: [loginCSS: 'login-min.css?v=1'])
    }
  }
}

but this isn't working.

This one works but it changes the source... I just want the files in the war to be modified.

import org.apache.tools.ant.filters.ReplaceTokens
war {
  webInf {
    from ("${webAppDir}/WEB-INF/jsp/includes/login_css_include.jsp") {
      it.eachFile {
        ant.replace(file: it.file, token: "@loginCSS@", value: "login-min.css?v=1")
      }
    }
  }
}

I'm brand new to gradle am I going about this totally incorrectly? Anyone needed to do something like this before? Using gradle 1.0-milestone-1.

Thanks