If you get a 500 error submitting the form
Uploading this to Heart the other day I got a 500 error, after talking to a muppet in support who said it was totally my fault and me coding in an error, then also accusing me of deleting the config file twice when I didn't even see it once, I pointed him to several versions, one on a development server, one with realtime, not sure if I also pointed him to rogerneedle.com which uses a very similar one on ukhosts4u, this thread which no ones reported it, that where working with no problems and all on different servers with different hosts he gave me the error code, but still insisted it was my error.
Now if you get a 500 error code it is down to how THEY have configured their server.
The fix to get around this bad configuration is to change how you write the headers .= variable to this:
$headers="MIME-Version: 1.0\r\nContent-type: text/html; charset=iso-8859-1\r\n".$email."\r\n";
It all needs to be on one line and the From: Your site needs to be removed as well otherwise it generates the error.
Anyone has this error let me know if this doesn't fix it and I'll have a look for you.

Thought I would update anyway.
Jaz