These functions are only available if the
interpreter has been compiled with the --with-cybercash=[DIR].
This extension has been removed from PHP as of PHP
4.3.0, if you have questions as to why then you will
find the following CyberCash Faq helpful. In short,
CyberCash was bought out by VeriSign and although the
CyberCash service continues to exist, VeriSign
encourages users to switch. See the above faq for
details.