libmcrypt is a powerful encryption library that is very popular with PHP-based applications. However, most Linux distributions do not include it. This causes problems for many users that need to download and compile it separately.
I am guessing that the reason it is not shipped is related to encryption or patent issues. However, the source code for library itself is hosted and available on sourceforge.net
I have been searching unsuccessfully for a document of authoritative post that explains the exact issues why this extension is not bundled with mainstream distributions. Can anyone provide a pointer to such material or provide an explanation?