user32: check for the file signature before load a cursor/icon from it (try2)

[Nikolay Sivov]

On Sat, Jul 2, 2011 at 4:29 PM, Vitaly Perov <vitperov at etersoft.ru> wrote:
> It fix crash in the russian accounting application "CheckXML+"
>
> --
> Best regards,
> Vitaly Perov
>

This patch needs a test I think.