This is what I remember, but it may not be accurate for some reason.
I was testing a level tonight, and when I was finished I had a blocker left with seven seconds left on the clock. At five seconds I initiated nuking. When the lemming blew up though the clock was at zero, and then it went to one minute five seconds! I have tried to recreate this glitch, but I haven't had any success yet. Just so Im sure I remembered correctly, if anyone has done this too tell me. If not, tell me any time glitches you know :-/