[SR-Users] Memory leak

Hello, We use Kamailio as a stateless load balancer. It runs on a VM, with 512 MB RAM, and it seems to have some kind of memory leak. The kamailio processes consume all available memory, until Kamailio crashes and restart. This occurs about once a day. Since it's stateless, and the restart is very fast, it's not a big deal, but I'd like to fix it. The strange thing is that I updated kamailio from 1.5.3 to 3.0.3 and the problem still ocurrs. I followed the instructions on http://www.kamailio.org/dokuwiki/doku.php/troubleshooting:memory in order to determine the cause, and stopped the traffic on the proxy. The allocated memory were not freed, after 1 hour the amount of free memory is still the same. Anybody has an ideia about what's happening, or how can I debug it? Thank you! Santiago Soares