[PHP-DB] Splitting a string by a ,

[Chris Payne]

Hi there everyone,

I'm trying to split a string into an Array by a , but I kepe getting errors.  Looking 
at the PHP manual, I thought it would be this way:

$keywords = preg_split(",", $email);

But it keeps saying that the , isn't an ending delimiter?

Any help would be appreciated, i'm trying to split email addresses from an input box 
seperated by a ,

Thanks for any help.

Chris