system gets panic

[César Amaya]

Hi list,

I have a HP dx5150 SFF system with FreeBSD 6.1 Release running on it. 
The system worked fine the first 4 weeks, after that, the server begun 
to reboot while it was booting, and two or three times 5 minutes  after 
booting. The error message said:

    panic: softdep_setup_inomapdep: found inode
    ...
    rebooting after 15 segs.

Do you know what´s going on here?
Thanks!