I've used the jquery-ui datepicker before. You can customize it to make the year a drop-down, similar to what you have. I forget what the default range of years is, but we modified it to suit our needs anyway...

But can't you just modify your widget? Somewhere in your code must be the range of years provided...

Ideally you could use the input element with type=datetime for browsers that support it, and a date widget fallback for browsers that don't. This should provide a better experience for users and hopefully less support issues for you.

Also, it allows you to set hour and minute of birth, but the rest of the site doesn't use them.

Since it has second-related marks, it would be nice if it was working with hours and minutes as well.