source: http://www.securityfocus.com/bid/16577/info
 
IBM Lotus Domino iNotes is prone to multiple HTML- and script-injection vulnerabilities.
 
These vulnerabilities can allow attackers to carry out a variety of attacks, including theft of cookie-based authentication credentials. 

Proof of concept for the email subject field script injection:

</TITLE><SCRIPT>alert("Vulnerable!");</SCRIPT>