GCC compile problem on AIX 6.1 as non root user. Getting cc1: error: /usr/local/include: Permission denied

On a p520 with AIX 6.1 I installed the GCC Packages from http://www.perzl.org/aix/index.php?n=Main.Gcc.

The had the version 4.2.4.

When trying to compile a simple c file I get the following message, when I'm a normal user:

[vsop:aixhaspa61:/entw/vsop/tmp]$ gcc -o a a.c
cc1: error: /usr/local/include: Permission denied
After searching for a solution, I found this thread, which has the same problem on solaris.  

After creating a /usr/local/include folder and changing the access rights,
the compilation also works for a non-root user.