I got errors when compiling ppl1.1 from a Mac OS.  Any idea how to fix this? 

In file included from Box.cc:25:
In file included from ./Box_defs.hh:2284:
In file included from ./Box_templates.hh:38:
In file included from ./BD_Shape_defs.hh:2368:
In file included from ./BD_Shape_inlines.hh:31:
In file included from ./Octagonal_Shape_defs.hh:36:
In file included from ./OR_Matrix_defs.hh:607:
./OR_Matrix_inlines.hh:100:9: error: missing 'typename' prior to dependent type template name 'OR_Matrix<T>::Pseudo_Row'
inline  OR_Matrix<T>::Pseudo_Row<U>&
        ^
./OR_Matrix_inlines.hh:101:1: error: expected unqualified-id
typename OR_Matrix<T>::Pseudo_Row<U>::operator=(const Pseudo_Row& y) {
^
1 warning and 16 errors generated.
make[3]: *** [Box.lo] Error 1
make[2]: *** [all] Error 2
make[1]: *** [all-recursive] Error 1
make: *** [all] Error 2

BR,