A: 

I don't think you have any control over that. And I think you should file a bug report with Apple over that. It should be smarter than that.

Squeegy
+1  A: 

Hmm, it works correctly in the Notes app. Not only is the background yellow, you also see the lines.

Maybe it depends on whether you set the background color directly on the UITextView or make it transparent and set the background color of its containing view?

oefe
+2  A: 

I just did a quick test in here and it's working fine.

I tested with firmware 2.2.1, in the simulator and using a device.

This is what I did to test it: 1- Created a new View-Based project 2- edited the nib in the Interface Builder, added a UITextView, setting the text to white and the background to gray, leaving everything else default

Do you have something different?

Alexandre L Telles
I was using a transparent background color with a UIImageView behind it. I still dont see any way to do this with an image background like in the notes app. Thanks for pointing this out.
Lounges