Found ACEZ in Placez, What is it?

Whatever ACEZ is, it always precedes what appears to be an actual page view so perhaps it's a filtering program of some sort. Additionally, it seems to only come via a proxy server.

Doesn't appear to be a bot but it's very strange.

Here's a few sightings:

220.227.148.74 "ACEZ" VIA=1.0 localzeesports.localzs.com:8080 (squid/2.5.STABLE1) FORWARD=192.168.10.178

212.138.113.12 "ACEZ" VIA=1.1 proxy2 (NetCache NetApp/5.3.1R4), 1.0 cache2.ruh FORWARD=213.165.59.253

212.138.113.13 "ACEZ" VIA=1.1 proxy2 (NetCache NetApp/5.3.1R4), 1.0 cache3.ruh FORWARD=213.165.59.253

212.138.47.17 "ACEZ" VIA=1.1 proxy2 (NetCache NetApp/5.3.1R4), 1.0 cache7.ruh FORWARD=213.165.59.253

212.138.47.14 "ACEZ" VIA=1.1 proxy2 (NetCache NetApp/5.3.1R4), 1.0 cache4.ruh FORWARD=213.165.59.253

Here's a sample of how it appears in a log file before a page is read:

212.138.113.13 - "GET /page1.html" "-" "ACEZ"
212.138.113.13 - "GET /page1.html" "" "Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)"

Any additional info would be nice if anyone knows anything about it.