When proxy.pac is used for java plugin such as:

function FindProxyForURL(url,host)
{
if(dnsDomainIs("java.com")){
   return "DIRECT";
}
return "PROXY doesnt_exist:80";
}

===
Using that proxy.pac in the web browser, and then setting the java plugin to use the browser's settings, I then go to:
http://java.com/en/download/help/testvm.xml

The java plugin starts up, and it incorrectly tries to make a connection using the doesnt_exist:80 proxy

It should read the dnsDomainIs and use a DIRECT connection instead of trying to use doesnt_exist:80 and then falling back to DIRECT mode after that.

console shows:
network: Connecting http://java.com/en/img/download/t6.gif with proxy=HTTP @ doesnt_exist:80
The example proxy syntax used above is incorrect.

dnsDomainIs takes two parameters.

function should be :

function FindProxyForURL(url,host)
{
if(dnsDomainIs(host, "java.com")){
   return "DIRECT";
}
return "PROXY doesnt_exist:80";
}