title: _WIN64 is not defined in x64 project
body: <p>I'm using VS2008 and the project properties are set for (active) x64</p>
  
  <p>and the weird thing is _WIN64 is not defined and WPARAM and LPARAM are still 32-bit.</p>
  
  <p>Should I define _WIN64 manually?</p>
  
  <p>If so, where should I put #define _WIN64? Preprocessor setting doesn't seem to work.</p>
  
  <p>I'm quite certain it's compiled as x64 because in task manager the exe has no *32 postfix.</p>