nginx 0.4.6 *) Bugfix: nginx did not run on 64-bit platforms except amd64, sparc64, and ppc64. *) Bugfix: nginx sent the chunked response for HTTP/1.1 request, if its length was set by text string in the $r->headers_out("Content-Length", ...) method. *) Bugfix: after redirecting error by an "error_page" directive any ngx_http_rewrite_module directive returned this error code; bug appeared in 0.4.4.

--- a/src/http/ngx_http_variables.c
+++ b/src/http/ngx_http_variables.c
@@ -640,7 +640,7 @@ ngx_http_variable_unknown_header(ngx_htt
             }
         }
 
-        if (n + prefix == var->len) {
+        if (n + prefix == var->len && n == header[i].key.len) {
             v->len = header[i].value.len;
             v->valid = 1;
             v->no_cachable = 0;