[Gmsh] mashing of a vast spheres array

[etoh]

First thanks a lot for a great piece of software.

I'm trying to mash a vast array of spheres. Mashing of arrays bigger 
than 21x24 spheres doesn't work.
After mashing, when I try to save the mash a message pops that the mash 
cannot be saved and the mash is consequently is not present on harddisk.
If the array is of 21x24 dimensions or less the mash is saved with no 
problems.
Is there a limit in the mash size?
Is there any workaround for this problem?

Denis