comment block detecting error

Code below will be detect as commented, but it actually not, I made a fix https://github.com/lessmind/php.vim/commit/0857201363b95160923d93f98342efd538e18dec for it, but I think there should have some better solution, any help?

``` php
<?php
//**
function foo() {
}
//*/
```
