dlopen returns NIL

[Google Code Exporter]

What steps will reproduce the problem?
1. Create new iPhone project
2. Add MSNetworksManager class
3. Compile and try to debug on real device
4. As a result, this string "libHandle = 
dlopen("/System/Library/Frameworks/Preferences.framework/Preferences", 
RTLD_LAZY);" returns NIL

What is the expected output? What do you see instead?
I expected to see an instance of lib handler and I can see NIL value

What version of the product are you using? On what operating system?
Latest version from SVN

Please provide any additional information below.
Maybe problem is that I need to use jailbreaked iPhone and I can't use such 
approach on legal device?

Original issue reported on code.google.com by [e-mail] on 4 May 2011 at 12:29