Linux server locks up...

Hi,
We are using RedHat 8 linux (kernel 2.4.18-14smp) on an IBM Netfinity box (dual CPU) as a media server. Our application on the server handles lots of RTP traffic by opening UDP sockets. It also uses the CURL libraries to ftp files from other locations at a very fast rate. We noticed that under heavy load the machine locks up. We cannot access it via telnet or any other interface. All we can do is restart the box. I don't see any kernel panic messages in the logs either. Any feedback on this issue would help me a great deal.

thanks