New Post: SPServices Issue with SP2007

I'm trying to get the current user and it doesn't appear to be working. Here's my code...

curUser = $().SPServices.SPGetCurrentUser({
   fieldNames: ['ID','Name','Title','EMail'],
   debug: false
});

Object doesn't support property or method 'replace' at line 21 character 47248

Is one of my properties that I'm retrieving coming back empty or something?