There are two similar security issues both taken care of by Suhosin patch and strict escaping/encoding rules. They both relate to injecting new lines into headers of network protocols. They are not very well known and i think its worth mentioning it.
HTTP response splitting is a web based attack where hacker manages to trick the server into injecting new lines into response headers along with arbitrary code. If you use GET/POST parameters in the headers like cookie or location, then someone could provide new lines with XSS attack.
Common example would be server redirecting to new location based on some variable (like url). To do it safely you should always encode/escape/cast strings before passing them into header PHP function.
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Hi, my name is Artur Ejsmont,
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