This question came up on the php.general list today. And i have seen it before when writing an shell script in PHP.
If you are sure the PHP executable can be found in that location. And the file is executable. But it still returns this error:
/usr/local/bin/php: bad interpreter: Permission denied
Big change the file you are trying to execute is on a filesystem with the noexec flag set. To fix this either set the exec flag for the filesystem or move the script to a place where it can be executed.