Does the Masked Input plugin do what you need or that one you have already found to be unreliable?
I do believe your best bet would be to use regular expressions inside of two separate formatting methods in order to achieve the desired results. This will be rather straight forward for phone numbers and I'll post a code example if one isn't posted by the time I sit back and have 10 minutes straight to write something up. Perhaps for the date field, you can use something like the jQuery UI Datepicker instead? http://marcgrabanski.com/pages/code/jquery-ui-datepicker