Problem with Bluetooth keyboards: "?" and "!" symbols doesn't appears in password fields

Hi:

I have a new iPad 2 running iOS 5.1.1. With my iPad, my friend gift me an iPad 2 Spanish Bluetooth keyboard and it works perfect but there is a problem.

I can use all symbols in text fields, but in password field I can't use "?" or "!" symbols; I need to show the tactil keyboard and then write this symbols with the tactil keyboard. A family borrow me another keyboard (other brand and model) and I have the same problem.

I tested both keyboards in an iPhone 4S running iOS 5.1.1 too and in this device the "?" and "!" symbols works perfect in any password field. I tested both keyboards in a friend's iPad 2 and the problem persist.

Therefore, I concuded that it's a bug in iOS 5.1.1 iPad Software (I only tested it in an iPad 2, it's probably it's happening in another model, too).

Did you know this bug? It's horrible to people like me that need to use these symbols in any passwords.

Thanks!

P.S. In password fields I can use other symbols like "@", "#", "~", "€", "$", "/", "(" , ")" , including "¿", "¡" ............. but "?" and "!" symbols are impossible.