mod_proxy and AAAA queries

[Chris Monson]

I have noticed that mod_proxy, in its apr_sockaddr_info_get calls uses 
unspecified resolution and sends it no flags.  This, of course, allows 
the APR to make the decision as to how to resolve the hostname, but it 
causes some truly amazing slowdowns when AAAA authorities are not 
available for particular hosts (for example, toolbar.aol.com).  The AAAA 
requests must time out before the A request can be made.

To solve this problem, I am interested in patching mod_proxy and 
friends, creating a new configuration directive, something like 
ProxyResolutionType (or order).  This would take a list of parameters 
indicating which kinds of queries will be tried, and would map to flags 
passed into apr_sockaddr_info_get.  Doing this would allow me to specify 
that I *never* want to make AAAA queries or A6 queries (or to specify 
that I want to make them after trying the currently more common A queries).

The patch is fairly trivial, but I wanted to get some feedback on the 
general idea before plunging forward with it.  One way or another, this 
is a problem that has really bitten me, so patch I will, but I would 
like to do it right and in a way that is useful for others.

Any thoughts?

C