i've logged a defect with regard to this problem. [NIM094284: Bing address locator always uses HTTP]in the meantime, you could use a technique similar to what is described in the forum thread Vinay linked to to manually update the url for the request in your code.esriRequest.setRequestPreCallback(myCallbackFunction);
...
function myCallbackFunction(ioArgs) {
if (ioArgs.url == "http://serverapi.arcgisonline.com/veadaptor/production/services/geocode/geocode") {
ioArgs.url = "https://serverapi.arcgisonline.com/veadaptor/production/services/geocode/geocode";
}
// don't forget to return ioArgs.
return ioArgs;
}
sorry for the inconvenience!