[Stk] rtduplex.cpp missing?

[Enrico Costanza]

Hello.

I just updated to the latest version of the stk,
from http://ccrma.stanford.edu/software/stk/release/stk-4.3.1.tar.gz

and I notice that RTDuplex.cpp is not there anymore, however it seems to 
be still in the documentation..
http://ccrma.stanford.edu/software/stk/classRtDuplex.html

is it just the file missing from the distribution file or a change in 
the API?

Thanks,
Enrico