sketch stays on Ethernet.begin when no ethernet connection

Projects Networking, Protocols, and Devices
1

I was trying out this Time NTP sketch: (http://arduino.cc/en/Tutorial/UdpNtpClient?action=sourceblock&num=1). If the ethernet cable is not plugged in, my sketch stays on if (Ethernet.begin(mac) == 0) and never moves on. I figured this would timeout after a while.
I have Arduino 1.01 with a Leonardo and Ethernet shield R3.

void setup() 
{
 // Open serial communications and wait for port to open:
  Serial.begin(9600);
   while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo only
  }
  // start Ethernet and UDP
  if (Ethernet.begin(mac) == 0) {
    Serial.println("Failed to configure Ethernet using DHCP");
    // no point in carrying on, so do nothing forevermore:
    for(;;)
      ;
  }
  Udp.begin(localPort);
}
2

Mine times out ok on a R2 ethernet shield and a Mega 2560. I disconnected the CAT5 and uploaded the sketch. It takes about a minute to print a fail. I checked with UdpNtpClient and DhcpAddressPrinter sketches.

edit: I removed the memory card from the microSD slot for both tests.

3

I tried it again and it timed out after 62 seconds. I guess I didn't wait long enough before.