phplot-5.0.5 cannot install

[maxrussell]

I'm trying to set up SNORT intrusion detection, following the BSD Hacks guide.

So far, I've had to substitute mysql5 for mysql4 as it is required elsewhere on my system.

However, more seriously I'm finding that:
phplot-5.0.5 cannot install

===>  phplot-5.0.5 cannot install: doesn't work with PHP version : 4 (Doesn't support PHP 4).
*** Error code 1

Stop in /usr/ports/graphics/phplot.

Has anyone got any alternative instructions for setting up the snort/acid system?