fseek compatibility

[Andrej Czapszys]

I think that I've run into a versioning problem.  I tried to search 
GNATS, but it seems to be unavailable.
I recently upgraded my debian linux box from libc-2.3.1 to libc-2.3.2, 
and now my Win4Lin binaries are
segfaulting inside fseek when reading the config file.

Here's what happens according to strace/gdb:
fh = fopen as _IO_old_fopen(filename=0x804916e "/etc/default/merge", 
mode=0x804910b "r") at fseek.c:39
fseek(fp=0x804a3a0, offset=0, whence=2) at fseek.c:41
 calls _IO_seekoff_unlocked (fp=0x804a3a0, offset=0, dir=2, mode=3)   
at ioseekoff.c:55

_IO_seekoff_unlocked looks at fp->_mode and fp->_wide_data, even though 
there were no such
fields in the structure created in _IO_old_fopen.  Therefore those 
fields are uninitialized, and I get this from gdb:
Program received signal SIGSEGV, Segmentation fault.
0x400714cd in _IO_seekoff_unlocked (fp=0x804a3a0, offset=0, dir=2, mode=3)
   at ioseekoff.c:55

55                          || (_IO_fwide (fp, 0) > 0 && 
_IO_have_wbackup (fp))))

Is this a known issue?  If not, should it be fixed with versioning like 
fopen/fclose are?

Thankyou,
Andrej