Yo can get static library mimicing Reeders status bar overlay, you can find it here
MTStatusBarOverlay
Or Just create a simple subclass of UIWindow with the following override of initWithFrame:
@interface ACStatusBarOverlayWindow : UIWindow {
}
@end
@implementation ACStatusBarOverlayWindow
- (id)initWithFrame:(CGRect)frame {
    if ((self = [super initWithFrame:frame])) {
        // Place the window on the correct level and position
        self.windowLevel = UIWindowLevelStatusBar+1.0f;
        self.frame = [[UIApplication sharedApplication] statusBarFrame];
        // Create an image view with an image to make it look like a status bar.
        UIImageView *backgroundImageView = [[UIImageView alloc] initWithFrame:self.frame];
        backgroundImageView.image = [[UIImage imageNamed:@"statusBarBackgroundGrey.png"] stretchableImageWithLeftCapWidth:2.0f topCapHeight:0.0f];
        [self addSubview:backgroundImageView];
        [backgroundImageView release];
        // TODO: Insert subviews (labels, imageViews, etc...)
    }
    return self;
}
@end
For More Information see this Link...
adding-view-on-statusbar-in-iphone
i hope this help you...