We're getting a few sporadic customer calls (less than 0.1% of our users) complaining of not being able to access my company's website - either they get a blank page (if they use IE), or a "Content Encoding Error" that says the page uses an invalid or unsupported form of compression (if they use FireFox).
The current suspicion is that when an HTTP 1.1 browser request comes through an HTTP 1.0 proxy, we're sending back the compressed HTTP 1.1 browser request, which is somehow being mangled by the HTTP 1.0 proxy.
The website is a Tomcat 4.2.2 back end with an IIS 6.0 front end with GZIP and DEFLATE enabled on the IIS servers.
Has anyone encountered this sort of error before? Is there a recommended fix to avoid breaking older proxy implementations?
Edit: We can replicate the issue with a default setup of squid-2.5, however newer versions of squid seem to work just fine.