Hi,
I think you should validate the text boxes onSubmit, not onBlur.If your want to focus a field then this is how you go about it.

Code:
  function check(t) /* this is called onBlur */
   {
     if(t.value.length<1)
     {
       alert("You can't leave the field empty");
       t.focus();
     }
   }
   /* t is the reference to the source element, so when calling the function 
   call it like this onBlur="check(this);"
   */
Check out this thread http://www.go4expert.com/showthread.php?t=452 for more help on form validation with javascript.

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