In iOS5 this works fine:

```
[descriptionWebView.scrollView setScrollEnabled:NO];

```

But in any iOS under 5 it fails with:

```
[UIWebView scrollView]: unrecognized selector sent to instance 0x791f9e0
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIWebView scrollView]: unrecognized selector sent to instance 0x791f9e0'

```