vchoi_fork

[svn-r12699] Description:
    Fix problems with opening a fractal heap multiple times, from different
file handles.

Tested on:
    FreeBSD/32 4.11 (sleipnir) w/threadsafe
    Linux/32 2.4 (heping) w/FORTRAN & C++
    Linux/64 2.4 (mir) w/enable-v1.6
    Mac OS/32 10.4.8 (amazon)