var __defaultFired = false; 
    var __nonMSDOMBrowser = (window.navigator.appName.toLowerCase().indexOf("explorer") == -1);        
    function WebForm_FireDefaultButton(event, target) { 
        if (!__defaultFired && event.keyCode == 13 && !(event.srcElement && (event.srcElement.tagName.toLowerCase() == "textarea"))) { 
            var defaultButton; 
            if (__nonMSDOMBrowser) { 
                defaultButton = document.getElementById(target); 
            } 
            else { 
                defaultButton = document.all[target]; 
            }                      
            if (defaultButton && typeof(defaultButton.click) != "undefined") {                    
                __defaultFired = true;                                                            
                defaultButton.click(); 
                event.cancelBubble = true; 
                if (event.stopPropagation) event.stopPropagation(); 
                return false; 
            } 
            else if(typeof(defaultButton.click) == "undefined"){ 
                if (window.navigator.userAgent.toLowerCase().indexOf("firefox") == -1)
                {
                    var clickevent=document.createEvent("MouseEvents") 
                    clickevent.initEvent("click", true, true)                                                                                      
                    __defaultFired = true;                                                            
                    defaultButton.dispatchEvent(clickevent) 
                    event.cancelBubble = true; 
                    if (event.stopPropagation) event.stopPropagation(); 
                    return false; 
                }
                defaultButton.click =  addClickFunction1(defaultButton);            
            } 
        } 
        return true; 
    }  

function addClickFunction1(bt) {
    //debugger;
    var result = true;
    if (bt.onclick) result = bt.onclick();
    if (typeof(result) == 'undefined' || result) {
        eval(bt.href);
    }
}