Qmail dies over and over

[Gustavo V G C Rios]

Hi folks, my freebsd box (3.2-Stable) running qmail dies over and over,
several about 1/2 times a week. Here is what i get at log:

937023957.591990 alert: oh no! lost spawn connection! dying...
937023957.617105 status: exiting


I decide to trace qmail syscalls, using the utility truss, i got that:

        returns 0 (0x0)
syscall stat("bounce/275998",0xbfbfd454)
        errno 2 'No such file or directory'
syscall write(0,0x804eba1,8)
        returns 8 (0x8)
syscall write(0,0x8055500,6)
        returns 6 (0x6)
syscall write(0,0x804e6c9,1)
        returns 1 (0x1)
syscall unlink(0x8051270)
        returns 0 (0x0)
syscall write(5,0x8051270,12)
        returns 12 (0xc)
syscall read(0x6,0x80550d0,0x400)
        returns 1 (0x1)
syscall gettimeofday(0xbfbfd970,0x0)
        returns 0 (0x0)
SIGNAL 20
syscall select(0x9,0xbfbfda30,0xbfbfd9b0,0x0,0xbfbfd99c)
        returns 1 (0x1)
syscall gettimeofday(0xbfbfd970,0x0)
        returns 0 (0x0)
syscall read(0x2,0x8054090,0x800)
        returns 0 (0x0)
syscall write(0,0x804e667,46)
        returns 46 (0x2e)
syscall utimes(0x8051270,0xbfbfd940)
        returns 0 (0x0)
syscall utimes(0x8051270,0xbfbfd940)
        returns 0 (0x0)
syscall utimes(0x8051270,0xbfbfd940)
        returns 0 (0x0)
syscall utimes(0x8051270,0xbfbfd940)
        returns 0 (0x0)
syscall utimes(0x8051270,0xbfbfd940)
        returns 0 (0x0)
syscall write(0,0x804efc6,16)
        returns 16 (0x10)
syscall exit(0x0)
        process exit, rval = 0


please, can anyone help me?
How to avoid these error? Before, what is happenning ?
Is this serious, or can be solved ?

Thanks a lot for your time and cooperation.