There is no MySQL injection attack. There is SQL injection attack. And it's not merely a problem of mysql but of how the code that uses mysql is written. And this affect all platforms. You should fix the developers to fix all sql injections.
A better approach is to either (1) add a mysql_prepare() function to the PHP MySQL extension, or (2) deprecate the extension in favour of one which forces or at least encourages or at least supports the use of prepared statements.