you can download a copy here - www.freakyclown.com/pcp-version.nse
example output here....
nmap -A -p 44321 192.168.56.101
Starting Nmap 6.00 ( http://nmap.org ) at 2013-06-05 21:39 BST
Nmap scan report for 192.168.56.101
Host is up (0.0028s latency).
PORT STATE SERVICE VERSION
44321/tcp open pcp SGI Performance Co-Pilot
|_pcp-version: 3.6.4
Service detection performed. Please report any incorrect results at http://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 42.64 seconds