Corrupt trajectory with @ character

Dear all

Some of our users (Local Ioannina cluster) complain about corrupted trajectory
file or log file
(lj + fene bond potential + fix langevin and xyz ascii dump )

Actually with a unpredictable and random way appear in the dump ascii file or
lmp out file, series of @ character ( probably some birary data translate into
to this character ), with out failure of the parallel lmp run

This behavior took place in different version of lammps with different version
of mpich2

Do you have any idea in which direction we have to search ... for this behavior

Thanks you in advance

Best

E.V.

p.s.

Last version of lammps is compile which gcc version 4.1.2 20080704 (Red Hat
4.1.2-50) on SL 5 and linked with mpich2 ver. 1.1.1p1