system hangs

I build a datlogging software on my mini2440.
From time to time the system hangs at all. 
I can't access through telnet, nor through ftp or webbrowser any more until
I reboot. I wonder if this is a problem of my own software or a problem of
the original linux image. if this is my own software, what could be the
problem to cause a complete system hang up?

Anyone has this problem too?

The 2440 Boots very fast.
The network usually takes a little longer to adapt to this situation.