We're currently developing a mobile webapp for a customer. The customer has Windows Mobile 8 phone.
    I don't have this kind of device to test on, but I tested in IE10, and the same bug occured there.
    Here's a patched version. Tested in IE10, latest version of Chrome, Firefox, and Opera. Also tested on Android native browser.
    XSP.moveToMPage = function sxy_rxy(view, moveTo, dir, transition, params) {
   // dojox.mobile._params = [];
    if (view == null){
    return;
    }
    
    var paramString = "";
   //check to see that if we have an object that it is a vanilla object
    if (params == null) {//nothing passed in for this arg
    params = "";
    }
    
    if( params.constructor === String ) {
    if (params.length > 0 && params[0] != "&"){//if we have a string make sure it starts right
    params = "&" + params;
    }
    }
    
    if (params instanceof Object && params.constructor === Object) {
    for (var k in params){
    paramString += "&" + k + "=" + params[k];
    }
    params = paramString;
    }
    
    if (params === "" || !params.match(/^(&(\w+)=(\w+))+/)){
    return;
    }
    
    view.performTransition(moveTo + params, dir, transition);
    };