运行webdriver时，运行3分钟后，出现以下异常，导致Webdriver崩溃。

我仅使用一个webdriver实例和一个FirefoxDriver配置文件。

Exception in thread "main" org.openqa.selenium.WebDriverException:
java.net.BindException: Address already in use: connect
System info: os.name: 'Windows XP', os.arch: 'x86', os.version: '5.1',
java.version: '1.6.0_18'
Driver info: driver.version: remote
        at
org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:
341)
        at
org.openqa.selenium.firefox.FirefoxDriver.execute(FirefoxDriver.java:
234)
        at
org.openqa.selenium.remote.RemoteWebDriver.findElements(RemoteWebDriver.java:
173)
        at
org.openqa.selenium.remote.RemoteWebDriver.findElementsByXPath(RemoteWebDriver.java:
231)
        at org.openqa.selenium.By$6.findElements(By.java:200)
        at
org.openqa.selenium.remote.RemoteWebDriver.findElements(RemoteWebDriver.java:
158)

Caused by: java.net.BindException: Address already in use: connect
        at java.net.PlainSocketImpl.socketConnect(Native Method)
        at java.net.PlainSocketImpl.doConnect(Unknown Source)
        at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
        at java.net.PlainSocketImpl.connect(Unknown Source)
        at java.net.SocksSocketImpl.connect(Unknown Source)
        at java.net.Socket.connect(Unknown Source)
        at
org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:
123)
        at
org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:
133)
        at
org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:
149)
        at
org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:
108)
        at
org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:
415)
        at
org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:
641)
        at
org.openqa.selenium.remote.HttpCommandExecutor.execute(HttpCommandExecutor.java:
211)
        at
org.openqa.selenium.firefox.internal.NewProfileExtensionConnection.execute(NewProfileExtensionConnection.java:
125)
        at org.openqa.selenium.firefox.FirefoxDriver
$LazyCommandExecutor.execute(FirefoxDriver.java:341)
        at
org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:
328)
        ... 11 more