Is the ECONNREFUSED problem a known issue with (i)WebDriver?

On my current project we're using iWebDriver to run acceptance tests on our CI server.

Occasionally, we see the error:

Connection refused - connect(2) (Errno::ECONNREFUSED)

Thus far, we have found no pattern to this failure; whenever we encounter it, we simply restart the build and it generally runs successfully. I'd say this happens roughly 10% of the time.

Before everybody jumps on me for ignoring a real problem: we capture screenshots whenever there is a test failure. Whenever this particular error occurs, there doesn't appear to be an actual problem based on the captured screenshot. It is not the same as a simple timeout error (where, e.g., an element isn't found in time); in that case we see a different message: execution expired (Timeout::Error).

We're all kind of under the assumption that this is due to some erratic bug in WebDriver itself. Which tempts me to implement a script that simply detects the above error message and restarts the build if it's detected but otherwise yields real failures. (Actually, I've already done that; I simply haven't configured our build server to use it, yet.)

Have o开发者_StackOverflowthers seen this intermittent error? Is it a known issue? Does it actually indicate a real problem that we should investigate on our end (in which case, where do we start)?