function isEmpty(str){
    strRE = new RegExp( );
    strRE.compile( '^[\s ]*$', 'gi' );
    return strRE.test( str.value );
} 
function validate( form ){
	if( isEmpty( form.username ) ){ alert( 'Please enter your username.' ); form.username.focus();return false; }
	if( isEmpty( form.password ) ){ alert( 'Please enter password.' ); form.password.focus();return false; }
    return true;
} 
function validate2( form ){
	if( isEmpty( form.username ) ){ alert( 'Please enter your username.' ); form.username.focus();return false; }
	if( isEmpty( form.password ) ){ alert( 'Please enter password.' ); form.password.focus();return false; }
	if( isEmpty( form.word ) ){ alert( 'Please enter security word.' ); form.word.focus();return false; }
    return true;
}