small letters -capital letters change in Flash CS5

you might have to explain exactly what you are trying a bit more

you can use the String's toUpperCase() function.

so if you have a textfield for example

myTextField.text = myTextField.text.toUpperCase();

if you want to force small letters to capitals as a user types in a textfield then you would need to add an event listener listening for teh change event and use the above code.

if you are after something else explain in more detail please