Tengo problemas para agregar objetos a la matriz NSMutableArray *.

//  Controller.m
#import "Controller.h"
@implementation Controller
- (void)parser:(NSString *)string{
    [array addObject:string]; 
    NSLog(@"answerArray(1): %@",[array objectAtIndex:1]);
    [array retain];
}
@end

//  Controller.h
#import <Foundation/Foundation.h>
@interface Controller : NSObject {
    NSMutableArray *array;
}
- (void)parser:(NSString *)string;
@end

NSLog (@ "answerArray (1):% @", [array objectAtIndex: 1]);

Resultados: answerArray (1): (nulo)