Gents, This appears to be an issue for Linux, Apache 2.2.15, compiled from source... extfiler=shared....
Whilst you are able to execute ExtFilters on local files, a Reverse Proxy configuration does not work the same way. This has been reported here: http://objectmix.com/apache/706472-proxypass-extfilter.html Config: <VirtualHost *:80> ServerAdmin webmas...@domain.com DocumentRoot /usr/local/apache/htdocs/ ServerName search.domain.com ServerAlias search.domain.com ErrorLog logs/search.domain.com-error_log CustomLog logs/search.domain.com-access.log combined <Proxy balancer://domain.com> BalancerMember http://ip1 BalancerMember http://ip2 </Proxy> ExtFilterDefine fixtext mode=output intype=text/html cmd="/bin/sed s/html/HTML/ig" SetOutputFilter fixtext RewriteEngine on ProxyPass / balancer://domain.com/ ProxyPassReverse / balancer://domain.com/ </VirtualHost> I am completely out of thoughts on this matter. If you guys could help, that would be wonderful.... Thanks! Vasiliy PS Removing the revproxy, and things work like a charm.