diff --git a/lib/parse/cjs.js b/lib/parse/cjs.js
index 462134e5..46f5af06 100644
--- a/lib/parse/cjs.js
+++ b/lib/parse/cjs.js
@@ -31,7 +31,7 @@ util.inherits(CJS, Base);
  */
 CJS.prototype.normalize = function (filename) {
 	filename = this.replaceBackslashInPath(filename);
-	if (filename.charAt(0) !== '/' && !filename.match(/^[a-z]:\//i)) {
+	if (filename.charAt(0) !== '/' && !filename.match(/^[a-z]+\//i)) {
 		// a core module (not mapped to a file)
 		return filename;
 	}