How to check what version of SunONE I am running

I don't have any where I can test this, so its mostly thoughts on what I'd try...

First backup cert8.db and key.db somewhere. Then delete the originals and try making something new:

% certutil -S -x -n nickname -t "u,u,u" -v num_of_valid_months -s subjectDN -d /opt/SUNWwbsvr/alias/https-sub.domain.ext-hostname-cert8.db [-h tokenname]

I'm looking through the possibilities at: http://developers.sun.com/appserver/reference/techart/keymgmt.html

Does that work? Does the following then work?

certutil -L -d /opt/SUNWwbsvr/alias/https-sub.domain.ext-hostname-cert8.db

If so, what happens if you restart the web server? Does it like the new cert? If it likes the cert, you could then try creating a signing request instead with 2048bits.

as @ceejayoz said 500 indicates the error response code. 32 is the size of the response in bytes.

I generated an example log for the "common" format log entry that sunone uses by default;

127.0.0.1 - - [10/Ma...100] "GET /Bg.png HTTP/1.1" 200 2445 <--- correct formatted HTTP request
127.0.0.1 - - [10/Ma...100] "GET /" 200 11172   <--- HTTP/1.0 request

The example request is missing a HTTP/1.1 from the request line, so its an old style (HTTP/0.9 compatible) HTTP/1.0 request. So it unlikely to be a request from a browser. It could be a manual telnet request e.g. telnet localhost 80, or someone using wget/curl in HTTP/1.0 mode, or a http client library.

As @mgorven mentioned, its a server error, hence it is either being returned locally from the default virtual server (because thats where the HTTP/1.0 requests end up) or from the remote proxied server.