vchoi_fork

[svn-r12733] Description:
    Use calloc() instead of malloc(), in order to fail a bit more gracefully
on errors.

Tested on:
    FreeBSD/32 4.11 (sleipnir) w/threadsafe
    Linux/32 2.4 (heping) w/FORTRAN & C++
    Linux/64 2.4 (mir) w/enable-1.6-compat