Apache mod-proxy ProxyErrorOverride for specific URL patterns

Question

I am using Apache 2.2 with mod-proxy and I have configured it with several ProxyPass statements to proxy from remote URL to local URL. I need to have custom error documents returned from Apache for these proxied URLs so I set "ProxyErrorOverride On" in my mod-proxy configuration along with some ErrorDocument directives (with local URL path) to return custom error pages for a few HTTP status codes of interest. However, when a status code is returned for which I have NOT created an ErrorDocument directive for, Apache replaces the response body with a default error page instead of leaving the original response body intact. This won't work with the application. So I really have 2 questions:

1) Is it possible to configure Apache to leave the original response body intact for a particular status code if I don't have an ErrorDocument override defined for it?

2) Is it possible to have the ProxyErrorOverride directive only apply to some of the URLs in my ProxyPass statements?

Answer 1

As arober11 pointed out in the comment above:

Afraid the answer is: No and No. If the directive could be limited to a location, directory, or set of URL's, then there would be something in the "Context" section, of the man page: httpd.apache.org/docs/2.2/mod/mod_proxy.html#proxyerroroverride

on the other hand: you can always add it to mod_proxy.c yourself.