[lammps-users] illegal minimize command

When I use minimize command without specifying ftol like minimize 1.0e-4 100 1000 it seems to be working fine in that it minimizes energy from o(e8) to o(e2) , but when I include ftol as well like

minimize 1.0e-4 1.0e-6 100 1000 or minimize 0.0001 0.00001 100 1000, it says "illegal minimize command"

What version of LAMMPS is this?

Hi James

That happens with both my lammps versions viz. 24Sept07 and 26Jun08
Since my minimizer minimizes energy from e8 to e2, does it mean that its
working fine, even if I am not including ftol in my arguments (and thus
making it only 3 arg input as written below) as needed?

Thank you