Android 4.0 ICS Webview with “Unknown chromium error: -324”-Collection of common programming errors

I coding a Browser use WebView in Android 4.0 ICS. But when I access some website,a error occurred.

I Override the onReceivedError method in WebViewClient, and I print the logcat.

08-28 09:22:00.549: D/chromium(22081): Unknown chromium error: -324

08-28 09:22:32.658: E/sky-mobi(22081): errorCode:-1 description:A network error occurred?failingUrl:https://172.16.28.5/portal/logon.htm

08-28 09:22:32.705: W/Web Console(22081): The page at "https://172.16.28.5/portal/logon.htm" displayed insecure content from file:///android_asset/webkit/android-weberror.png.

08-28 09:22:32.705: W/Web Console(22081):  at null:1

I test the URL with Android 2.3.3 ,and it totally work fine?