system log help

well my computer has been crashing a lot recently (i noticed it seems to be mostly while safari and itunes are running at the same time but i have no idea if this is the cause of the problem or just a coincidence). I read one thing that told me to check my system logs, so i did and the only thing that i found weird that was around the time i crashed was this, but i have no idea what it means.

May 25 20:18:39 (my-name's)-computer [0x0-0xa00a0].com.apple.Safari[2456]: Number of lights added exceeds maximum!
May 25 20:20:29: --- last message repeated 28 times ---

can anyone help me out?

 

well i play runescape, which is a browser based java game, so i guess that window is open a lot, many times when it crashes however i'm not at the computer so its just sitting at the login screen