I am salesforce (SFDC) developer. In my visualforce page for input box I am using placeholder code.
As IE9 doesn't support the placeholder attribute, you can do it in Javascript/jQuery like so (quickly written, not tested):
if(navigator.appVersion.match(/MSIE [\d.]+/)){
var placeholderText = 'Some Placeholder Text';
$('#first_name').val(placeholderText);
$('#first_name').blur(function(){
$(this).val() == '' ? $(this).val(placeholderText) : false;
});
$('#first_name').focus(function(){
$(this).val() == placeholderText ? $(this).val('') : false;
});
}
Do the same for the blur event too, then that will mimic a placeholder attribute.
[Edit]
Okay, after rethinking this (due to the comment) this is really not the most elegant solution (however it does work), so I would disregard this answer totally.