diff --git a/Jakefile b/Jakefile
index 207cfce2e7f40..16330305b6a08 100644
--- a/Jakefile
+++ b/Jakefile
@@ -366,7 +366,7 @@ desc("Builds the test infrastructure using the built compiler");
 task("tests", ["local", run].concat(libraryTargets));
 
 function exec(cmd, completeHandler) {
-    var ex = jake.createExec([cmd]);
+    var ex = jake.createExec([cmd], {windowsVerbatimArguments: true});
     // Add listeners for output and error
     ex.addListener("stdout", function(output) {
         process.stdout.write(output);
@@ -488,18 +488,25 @@ task("runtests-browser", ["tests", "browserify", builtLocalDirectory], function(
     exec(cmd);
 }, {async: true});
 
+function getDiffTool() {
+    var program = process.env['DIFF']
+    if (!program) {
+        fail("Add the 'DIFF' environment variable to the path of the program you want to use.")
+    }
+    return program;
+}
 
 // Baseline Diff
-desc("Diffs the compiler baselines using the diff tool specified by the %DIFF% environment variable");
+desc("Diffs the compiler baselines using the diff tool specified by the 'DIFF' environment variable");
 task('diff', function () {
-    var cmd = "%DIFF% " + refBaseline + ' ' + localBaseline;
+    var cmd = '"' +  getDiffTool()  + '" ' + refBaseline + ' ' + localBaseline;
     console.log(cmd)
     exec(cmd);
 }, {async: true});
 
-desc("Diffs the RWC baselines using the diff tool specified by the %DIFF% environment variable");
+desc("Diffs the RWC baselines using the diff tool specified by the 'DIFF' environment variable");
 task('diff-rwc', function () {
-    var cmd = "%DIFF% " + refRwcBaseline + ' ' + localRwcBaseline;
+    var cmd = '"' +  getDiffTool()  + '" ' + refRwcBaseline + ' ' + localRwcBaseline;
     console.log(cmd)
     exec(cmd);
 }, {async: true});