applied the filter_finalize_hang patch to the nginx core. see http://mailman.nginx.org/pipermail/nginx-devel/2012-May/002190.html for details.

patches/nginx-1.0.15-filter_finalize_hang.patch

@@ -0,0 +1,10 @@
+--- nginx-1.0.15/src/http/ngx_http_request.c	2012-03-05 20:49:32.000000000 +0800
++++ nginx-1.0.15-patched/src/http/ngx_http_request.c	2012-05-11 20:50:01.478111234 +0800
+@@ -1900,6 +1900,7 @@
+ 
+     if (rc == NGX_OK && r->filter_finalize) {
+         c->error = 1;
++        ngx_http_finalize_connection(r);
+         return;
+     }
+ 

util/mirror-tarballs

@@ -63,6 +63,9 @@ patch -p1 < $root/patches/nginx-$main_ver-log_escape_non_ascii.patch || exit 1
 echo applying reset_wev_handler_in_named_locations.patch ...
 patch -p1 < $root/patches/nginx-$main_ver-reset_wev_handler_in_named_locations.patch || exit 1
 
+echo applying filter_finalize_hang.patch ...
+patch -p1 < $root/patches/nginx-$main_ver-filter_finalize_hang.patch || exit 1
+
 #echo "INFO: applying null-character-fixes patch"
 #patch -p0 < $root/patches/nginx-$main_ver-null_character_fixes.patch || exit 1