Do yourself a favor and watch this YouTube video that I will link. After you click it fast forward that vieeo to about 8:32. The video is a High Times production and very educational.
YouTube - Ready Set Grow - Vol 2 (5/8) (8:32)
How old are the seeds exactly? If they are kept in a cool, dark place I heard seeds can last for at least 2 years. They may take a while longer to pop or they may be duds. Good call on ordering a new batch.
Do yourself a favor and YouTube Ready-Set-Grow Vol 2, submitted by Weed22man. The video is a HighTimes production.
Here's the link. Fast forward about 3:20 into the video for Grow Room Security.
http://www.youtube.com/watch?v=xMQ5SZm8dkU