Regional differences dictate the proper way to write a date in a particular locality. In the United States it would usually be written January 14, 1990. From what I have seen the European standard would be 14, January, 1990.
The first form, with the month first, corresponds to the American way of writing dates so I suspect they would have no problem with it being written in that way (Confirmation please, Amis). I would not do so. The comma after 14 is essential.
The second form is more European and more formal, but even so I would consider the comma to be optional (the rule says it belongs there, but I wouldn't use it).