I have today revisited the reverse proxy on Apache 2.0 (for which mod_proxy_html was originally written).
The good news: the current versions of mod_proxy_html (3.1.2) and mod_xml2enc (1.0.3) build and work nicely with Apache 2.0. I have hitherto recommended Apache 2.0 users mod_proxy_html 2.5 as the ’safe’ solution.
The bad news: working with Apache 2.0’s proxy just seems incredibly limiting, and calls for a whole bunch of hacks/workarounds. I’d forgotten that …
(not that 2.2 is free of them – looking forward to 2.4 and the expression engine).