You should state the license explicitly, somewhere

[tv42]

Your LICENSE file is GPLv2, but the problem with that is that it's a license with optional parts. See "How to Apply These Terms to Your New Programs" -- though putting a copyright in every single file is not needed, you should state it once somewhere.

Quoting the license itself (my emphasis):

If the Program specifies a version number of this License which applies to it and "any later version", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation.