Dress code for New York Bar?

We wanted to visit the New York Bar in the Park Hyatt Shinjuku last time we were there but couldn't make it. I seem to remember that there is a dress code to enter the bar. Could someone please tell what it is? Also, are reservations possible and recommended?

I could not find any info. on the hotel websitse, but one traveler says "no jeans" on his travel blog:

http://www.travelblog.org/Asia/Japan/Tokyo/Shinjuku/blog-161...

This one here only says "beware there is a dress code" - by the way the cover charge is mentioned on the hotel website:
http://www.asiarooms.com/japan/tokyo/park_hyatt-hotel-review...

I always wonder. Why don't people email instead of asking anonymous people on an internet forum?
http://www.tokyo.park.hyatt.com/hyatt/hotels/index.jsp

That's what this forum is for, isn't it? Besides, most of the time, answers here are faster and it is kind of a one stop place for all things Japan. I also enjoy it to give feedback if I know the answer to a question.

I'm not positive about the dress code, but be aware that there is a 2000 yen per person cover charge after 7:00. It applies whether or not you are staying at the hotel.

Yes, I know, thanks! On Sundays, the cover fee already applies from 18:00. But that's ok, there is live music and I heard the drink prices are reasonable.

These are the official dressing rules according to the Park Hyatt Tokyo:

We kindly ask all guests to refrain from wearing the following garments when patronizing
the hotel's restaurants, lounge and bars:

Beach sandals or slippers
Male sleeveless tops
Sportswear such as running shorts
Torn or cut - off jeans or any other garments in improper condition
Male dress shorts (after 5:00 pm.)

We would appreciate your understanding in advance.

In addition, New York Bar is open daily from 5:00 pm with live jazz performances from 8:00 pm (from 7:00 pm on Sundays).
Please note that no reservations are taken for the bar and guests are escorted to the bar on a walk-in basis.

I would also like to take this opportunity to inform you that we have a cover charge of 2,000 per
person for the live entertainment.