On focus JavaScript Error

Question

I have a dojo dropdown list widget here is the code:

 dojo.forEach(
        dojo.query(".select-frame-inner-border ",_this._container),
        function(obj){
            evt = dojo.connect(obj,"onmouseenter",function(){
                if (_this._disabled){return;}
                _this.hasManualFocus = true;
                **_this.obj._el.focus();**
                _this.setState(0);
                if (dojo.isIE){
                    //Closing the dropdown for IE for performance gains
                    _this.close();
                }
            });
            _this.events.frame.onmouseenter.push(evt);

            evt = dojo.connect(obj,"onmouseleave",function(){
                if (_this._disabled){return;}
                _this.hasManualFocus = true;
                _this.obj._el.focus();
                _this.setState(-1);
            });
            _this.events.frame.onmouseleave.push(evt);
        }
    );
//alert(this.obj._links.length);
    dojo.forEach(
        this.obj._links,
        function(opt){

            evt = dojo.connect(opt,"onclick",function(e){
                e.preventDefault();
                if (!this || !this.parentNode){
                    return;
                }
                if(dojo.hasClass(this.parentNode , "disabled") == false){
                    _this.select(this);
                }
                return false;
            });
            _this.events.options.push(evt);
        }
    );

where you see the bold is where I am getting the error. I have two security questions that I am asking on my registration form. And these have several options in the dropdown selection list. What is happening is the validation error is firing after the first security question and before the second security question is addressed by the user if the user mousesout and then mousesback in.