Just quick thought for your reference.
1) yes, a little confused.Intel 64( or"em64t") is really X64.
There are some information talking about IA32, Intel 64(em64t the previous name), IA64 . But seems we need to make it seperated.
Which Intel IPP package should I download?
For example, for Intel Pentium 4 processor systems running Linux*, the install executable file is named l_ipp_ia32_p_x.x.xxx.tgz. Itapply to Mac OS too.
I am not sure, how you will resolve this issue , only way is to upgrade Xcode.
As you said, this version of IPP require Xcode 3.1.x as mentioned in the below table.