I'm facing the problem of NULL being defined twice. The scenario arises when part of the project is in C code. Consequently, I have to include stdio.h in my file. Obviously, NULL is defined in this file. Now, this NULL is also defined in e32std.h and that too without an #ifndef.
Hence, a build would result in a clashing of definitions of NULL. I think life would have been much easier had e32std.h contained a #ifndef to check if NULL has already been defined.