EXC_BAD_ACCESS when opening modal view

I'm having a problem with my iPhone App, I'm getting EXC_BAD_ACCESS, I had some memory leaks, but these are now fixed, so I'm not sure whats going on. I realise that I haven't provide a lot of information, but I really don't know whats happening.

The initial screen opens up where I have a number of buttons. Tapping on the first button, which runs the following code and opens up a modal view:

-(IBAction)newWorkoutButton

{

    newWorkoutViewController .loadedFromRootViewController = @"YES";

    [self presentModalViewController:newWorkoutViewController animated:YES];

}

The screen freezes and the is in the code below:

#import <UIKit/UIKit.h>

#import <objc/runtime.h>

#import <CoreLocation/CoreLocation.h>





int main(int argc, char *argv[]) 

{

    Method getDistanceFrom = class_getInstanceMethod([CLLocation class], @selector(getDistanceFrom:));

    class_addMethod([CLLocation class], @selector(distanceFromLocation:), method_getImplementation(getDistanceFrom), method_getTypeEncoding(getDistanceFrom));



    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];

    int retVal = UIApplicationMain(argc, argv, nil, nil); // ERROR HAPPENING HERE

    [pool release];

    return retVal;

}