Exec commandLine issues with periods on Windows

Take the following build.gradle file using v2.5:

apply plugin: 'base'

task testPython(type: Exec) {
    commandLine 'python2.7', 'test.py', '-h'

This executes just fine on Linux. However on Windows I copied the python.exe and renamed it to python2.7.exe. However, Gradle is unable to find this application since I believe it is looking for python2.7 without the exe extension. If I name the application python2.7 (without the exe) it works fine.