Thanks for the advice.
As per your suggestion, I've installed the 1.2.6-1 squeeze package from nginx.org and the problem persists.
I will follow up with the results of a source build.
-s
=======================================================================================
wget http://nginx.org/packages/debian/pool/nginx/n/nginx/nginx_1.2.6-1~squeeze_amd64.deb
--2013-01-22 18:38:49-- http://nginx.org/packages/debian/pool/nginx/n/nginx/nginx_1.2.6-1~squeeze_amd64.deb
Resolving nginx.org (nginx.org)... 206.251.255.63
Connecting to nginx.org (nginx.org)|206.251.255.63|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 485238 (474K) [application/octet-stream]
Saving to: ���nginx_1.2.6-1~squeeze_amd64.deb���
100%[========================================================================================================>] 485,238 614KB/s in 0.8s
2013-01-22 18:38:50 (614 KB/s) - ���nginx_1.2.6-1~squeeze_amd64.deb��� saved [485238/485238]
==============================
root@skokomish:/tmp# !dpkg
dpkg -i `ls *deb`
(Reading database ... 136211 files and directories currently installed.)
Preparing to replace nginx 1.2.6-1~squeeze (using nginx_1.2.6-1~squeeze_amd64.deb) ...
Unpacking replacement nginx ...
Setting up nginx (1.2.6-1~squeeze) ...
===============================
root@skokomish:/tmp# /etc/init.d/nginx start
root@skokomish:/tmp# !netstat
netstat -pant |grep nginx
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 15578/nginx.conf
tcp 0 0 66.113.100.140:81 0.0.0.0:* LISTEN 15578/nginx.conf
root@skokomish:/tmp#