lighty SHOULD not include "Content-Encoding" in a 304 Not Modified response
According to RFC2616, a 304 Not Modified response SHOULD/MUST NOT include other entity-headers for a strong/weak cache validator request to prevent inconsistencies between cached entity-bodies and updated headers.
However, for a GET request w/ Accept-Encoding header, lighty w/ mod_compress includes Content-Encoding entity-header field within a 304 response. And this DOES confuse some proxy software, including squid, and client browsers about their cached objects.
Simple patch file is attached.
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