phPOP3clean is a spam, virus, and worm filtering system for POP3 email accounts. It is designed to run as a cron job and can catch spam based on links to blacklisted IPs, obfuscated words, or blacklisted phrases in the message body as well as attached-image spam, email worms, and corrupted or malformed emails.
PEAR Validate is a set of useful methods to validate various kinds of data. It supports numbers (min/max, decimal, or not), email addresses (syntax, domain check, RFC 822), strings (alpha, upper and/or lowercase, numeric), dates (min, max), URIs (RFC 2396), and more. It also has many locale validation rules, specialized for each country or region (US, FR, UK, DE) or application domain (such as finance).
PHP MIME Mail decoder class is a PHP class to parse and decode MIME email messages. It supports decoding single RFC 2822 MIME messages or archives that aggregate multiple messages in the mbox format. It can decode messages read from files or data strings. The bodies of multipart messages can be decoded into distinct sub-messages. Optionally, the message body data can be saved to separate files, so the class can handle messages larger than the available memory. The parser can tolerate some syntax errors in malformed messages that are not compliant with RFC 2822.
Horde Groupware Webmail Edition is an enterprise ready browser-based communication suite. Users can read, send, and organize email messages and manage and share calendars, contacts, tasks, and notes with the standards compliant components from the Horde Project. It bundles the separately available applications IMP, Ingo, Kronolith, Turba, Nag, and Mnemo. It can be extended with any of the released Horde applications or the Horde modules that are still in development, like a file manager, a bookmark manager, a forum, or a wiki.
htmLawed is a PHP script that makes input text more secure, HTML standards-compliant, and suitable in general from the viewpoint of a Web-page administrator, for use in the body of HTML 4 or XHTML 1 or 1.1 documents. It is a customizable HTML/XHTML filter, processor, purifier, and sanitizer. It can ensure that HTML tags are balanced and properly nested tags, neutralize code that may be used for cross-site scripting (XSS) attacks, and limit the allowed HTML elements, tags, attributes, or URL protocols.