Unable to read symbols warning with XCode 3.2.5 and iOS 4.2.1

If you get one of the following messages in the console while starting your program : 

warning: Unable to read symbols for /Developer/Platforms/iPhoneOS.platform/DeviceSupport/4.2.1 (8C148)/Symbols/usr/lib/info/dns.so (file not found).

or

warning: Unable to read symbols for /Developer/Platforms/iPhoneOS.platform/DeviceSupport/4.2.1 (8C148)/Symbols/Developer/usr/lib/libXcodeDebuggerSupport.dylib (file not found).

These are known problems by Apple, but they shouldn't prevent debugging. I spent some time on trying to solve these problems before I realised that indeed debugging was still working. Even using the new "Collect" feature in the Organizer for an unknown (minor) iOS version did not solve this problem. I guess it's just a bug we must live with until the next release of XCode.