Httpd – apache httpd+mod_proxy+mod_ntlm

Does adding 'nocanon' to your ProxyPass rule work?

i.e. ProxyPass /app ajp://127.0.0.1:8080/app nocanon

From the docs:

Normally, mod_proxy will canonicalise ProxyPassed URLs. But this may be incompatible with some backends, particularly those that make use of PATH_INFO. The optional nocanon keyword suppresses this, and passes the URL path "raw" to the backend. Note that may affect the security of your backend, as it removes the normal limited protection against URL-based attacks provided by the proxy.

NTLM is connection based therefore not suitable for HTTP-level proxying in general. HAProxy can do TCP reverse proxying which should work just fine. When used as a forward proxy for this situation it's not really packed with features (i.e caching, access control, filtering, etc). It should be just fine to use instead of Apache though.