fileutils doesn't compile properly on AIX 4.3.3

[LTARDRES]

Hi,
I tried to compile findutils v 4.1 and 3.16 on AIX 4.3.3 ML 7
The compilation of lib/mountlist.c fails saying MOUNTED is undefined

I found the following workaround :

MOUNTED is used in a #ifdef MOUNTED_GETMNTENT1 so I commented out 
#define  MOUNTED_GETMNTENT1 1
in config.h

Does anyone know :
1. If what I did is "safe" (I just needed ls and it seems to work ok)
2. where the problem is and why it hasn't been addressed (unless it comes
from my system).

Thank you

Lucien