[OSX] does a toolchain need to support NPTL for OM?

[Dr. H. Nikolaus Schaller]

Hi,
I am in the process of building a native crosstoolchain for the  
Freerunner to do some Objective-C development that runs natively on a  
Mac OS X (Darwin).

Currently I am sitting at the issue that glibc-2.3.6 with NPTL has no  
support for ARM processors and I thought that every kernel since 2.5  
needs NPTL.

So my questions - where I hope someone can help:
a) does the FR need or support NPTL for ARM?
b) where can I find a patch to include in glibc-2.3.6?

Nikolaus

PS: There is no need to refer to crosstools or Open Embedded since  
neither one works on Darwin.