iPhone 4, 01.59.00 jailbreak

[gray_mouse]

Last time I jailbreaked was in May last year, a lot of time went by, you can say that I'm a noob now.

My iPhone relies on software unlock via ultrasn0w. Modem firmware 01.59.00, and iOS version 4.3.2...

I need to know which latest iOS version I can put on it and still keep my phone unlocked?