Same here. It seems its for all dedicaded root servers.
If you look here: http://tools.poweredbygamespy.com/masterserver/index.aspx?gamename=arma3pc

All Servers with 0.0.0.0 at icmpip works fine with a normal ping. All servers with an ip there have 2500ms ping.

I search at google for a long time but theres nothing about the icmpip at gamespy master list. But it seems, all gameserver-hoster like "vilayer" or "gameservers" have 0.0.0.0 at icmpip.
We have shut down the firewall completly but the ping is the same on 2500 on our root-server. Any sugestions? Without any firewall, the problem should be solved, easier then the idea from dwarden.