Serverless dataset load fails for Internet Explorer if using SSL and the server issues a 'Pragma: no-cache' http header.
The same exact query will work fine under IE http & Firefox http or https. Only IE https fails.
This is NOT a crossdomain.xml issue.

I am using WinXP IE6.0 + FlashPlayer 8 + Laszlo 3.1
But it was also failing under Laszlo 3.0 + FlashPlayer 7 (I've had this problem for months, but I just finally figured out I could avoid it by getting rid of the "Pragma: no-cache" in the http headers returned by the app server)

Here's some example code:
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PHP for the server side ("/prag-nc-test.php"):
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<?
// Pragma: no-cache breaks serverless loads under https in IE,
// but works for http in IE and http and https in Firefox

//header('Pragma: no-cache');

print('<result>Irrelevant</result>');
?>
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LZX Client:
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<canvas height="350" width="100%" debug="true" proxied="false">
  <debug x="5" y="40" height="300" width="800"/>
  <dataset type="http" name="testds"
autorequest="false"
ontimeout="canvas.handleTimeout()"
          onerror="canvas.handleError()"
          ondata="canvas.handleData()"
          src="/prag-nc-test.php"/>

  <method name="handleData">
    Debug.write((new Date())+": Request succeeded.");
  </method>
  <method name="handleError">
    Debug.write((new Date())+": Request got an error -- sorry.");
  </method>
  <method name="handleTimeout">
    Debug.write((new Date())+": Request timed out (after "+(getTimer()-canvas.reqTime)+" ms) -- sorry.");
  </method>

  <view x="5" y="5">
    <text valign="middle">Request URL:</text>
    <edittext width="300" id="srcTxt" text="$once{canvas.datasets.testds.src}"/>
    <button text="Start Request">
      <method event="onclick">
canvas.reqTime = getTimer();
        var d = canvas.datasets.testds;
        if (srcTxt.text) {
          Debug.write((new Date())+": Setting URL to '"+srcTxt.text+"'...");
          d.setAttribute('src', srcTxt.text);
          Debug.write((new Date())+": value set.");
        }
        Debug.write((new Date())+": Sending request to "+d.src+"...");
        d.doRequest();
      </method>
    </button>
    <simplelayout axis="x"/>
  </view>
</canvas>
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