You want to avoid certain kinds of setuid root spoofing attacks.
Pass a single trailing dash to the shell, as in: #!/bin/bash –
The first line of a script is a magic line (often called the shebang line) that tells the kernel what interpreter to use to process the rest of the file.
The kernel will also look for a single option to the specified interpreter.
There are some attacks that take advantage of this fact, but if you pass an argument along, they are avoided.
See http://www.faqs.org/faqs/unix-faq/faq/part4/section-7.html for details.