Where to get working sources for NIOS2 toolchain?

i found via google this page:

http://www.altera.com/support/kdb/2000/11/...72000_7307.html (http://www.altera.com/support/kdb/2000/11/rd11272000_7307.html)

there i can download the source code to the gnu toolchain used in the NIOS2 development tools ... however, the 5.0 and 5.1 source trees are both incomplete ... for example, the src/gcc/gcc/config/nios2/t-nios2 config file refers to these files:

$(srcdir)/config/nios2/lib2-divmod.c

$(srcdir)/config/nios2/lib2-divmod-hi.c

$(srcdir)/config/nios2/lib2-divtable.c

$(srcdir)/config/nios2/lib2-mul.c

$(srcdir)/config/nios2/crti.asm

$(srcdir)/config/nios2/crtn.asm

which do not exist in either the 5.0 or 5.1 source tarballs

so where can one obtain the complete source trees ?