jQuery(id).blur, jQuery(id).focus invokation issue

jQuery(id).blur, jQuery(id).focus invokation issue

Here is my jascritpt code
<script language="text/javascript">
//<![CDATA[
jQuery(document).ready(function() {
jQuery('#text-area-id').blur(function() {
if (jQuery(this).val() == '') {
jQuery(this).attr('value', 'Default Text');
}
});
jQuery('#text-area-id').focus(function() {
if (jQuery(this).attr('value') == 'Default Text'') {
jQuery(this).val('');
}
});
}
//]]>
</script>
I am showing 'Default Text' in text area, and when focus is there it
will clear the text area and shows empty text area for user input, and
on Blur it will reset to "Default Text" if the input is empty. This
whole javascript is in model dialog. This works only one time , ie.
first time when DOM is loaded, and following invocations it failed
invoke blur and focus. Please let me know what is issue with this
approach.
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