Problems with mod_proxy - invalid response from an upstream server

I am receiving the error in my browser of

502 Proxy Error
Proxy Error
The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request GET
/MyProfile/MyDetails/MyDetails.do;jsessionid=1l5bqi2eonag5.
Reason: Error reading from remote server

The webserver is Apache 2.2.13 running on RHEL 5.3
The application server is a vendor supplied software package called
AlarmPoint Enterprise v3.2.1 (http://www.alarmpoint.com). It utilizes
Jetty.
The webserver is fronted by a load balancer. The front-end host is
configured on the load balancer, SSL termination is done on the load
balancer's SCA. Communication between the load balancer and webserver
is clear-text (remember, SSL on the load balancer) and communication
between apache and the app server is clear text as well (internal
secure network).
The issue is present if i access the webserver directly or through the
load balancer. Both provide the exact same errors.
The issue is never present if i access the app server directly.
The issue seems to be resolved in Firefox only if, I configure via
"about:config" the option network.http.sendRefererHeader to "0" it
will then work fine in Firefox.

The URL users access on the load balancer is
https://website.domain.com (obviously modified for this forum).
The URL to access directly on the webserver is http://webserver.domain.com:23012
The URL to the app server directly is http://appserver.domain.com

The Apache configuration file httpd.conf has an Include for a
proxy.conf which is displayed below
===== [ proxy.conf ] =====
LoadModule proxy_module modules/mod_proxy.so
LoadModule proxy_http_module modules/mod_proxy_http.so
LoadModule proxy_connect_module modules/mod_proxy_connect.so
ProxyPass / http://appserver.domain.com/
ProxyPassReverse / http://appserver.domain.com/

The error_log is displayed below
===== [ error_log ] =====
[Tue Mar 16 15:47:27 2010] [error] [client 10.224.24.87] (70014)End of
file found: proxy: error reading status line from remote server
appserver.domain.com, referer:
https://website.domain.com/MyProfile/index/index.do;jsession id=1l5bqi2eonag5
[Tue Mar 16 15:47:27 2010] [error] [client 10.224.24.87] (70014)End of
file found: proxy: error reading status line from remote server
appserver.domain.com, referer:
https://website.domain.com/MyProfile/index/index.do;jsession id=1l5bqi2eonag5
[Tue Mar 16 15:47:27 2010] [error] [client 10.224.24.87] (70014)End of
file found: proxy: error reading status line from remote server
appserver.domain.com, referer:
https://website.domain.com/MyProfile/index/index.do;jsession id=1l5bqi2eonag5
[Tue Mar 16 15:47:27 2010] [error] [client 10.224.24.87] proxy: Error
reading from remote server returned by
/MyProfile/MyDetails/MyDetails.do;jsessionid=1l5bqi2eonag5, referer:
https://website.domain.com/MyProfile/index/index.do;jsession id=1l5bqi2eonag5

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