fixed edge case in xunit export

@@ -72,6 +72,7 @@ XXXX-XX-XX, v1.0.1
 - fixed [#336](https://github.com/n1k0/casperjs/issues/336) - Test result duration may have an exotic value
 - Added `casper.mouse.doubleclick()`
 - fixed [#343](https://github.com/n1k0/casperjs/issues/343) - Better script checks
+- fixed an edge case with xunit export when `phantom.casperScript` may be not defined
 
 2012-12-24, v1.0.0
 ------------------

@@ -45,7 +45,8 @@ var TestSuiteResult = require('tester').TestSuiteResult;
  */
 function generateClassName(classname) {
     "use strict";
-    var script = classname.replace(phantom.casperPath, "").trim() || phantom.casperScript;
+    classname = (classname || "").replace(phantom.casperPath, "").trim();
+    var script = classname || phantom.casperScript || "";
     if (script.indexOf(fs.workingDirectory) === 0) {
         script = script.substring(fs.workingDirectory.length + 1);
     }