Match regular expression in javascript

i am using javascript to validate my form fields, and the below regular expression is not working, why? am i used the wrong way to match it?

var name=document.getElementById('first_name').value;

             if (!name.match(/^[A-Za-z]*$/))
                document.getElementById('error').innerHTML="Please match the regxp";
                return false;

Exactly how isn’t it working?

match returns either an array of the matches found or null if no matches are found - an array will convert to true and null to false for the purpose of the if statement and so provided only letters are entered into the field the content of the if statement will not be run. Any non letter character anywhere in the field (such as a leading or trailing space) will cause the the match to fail.