Tango I/O bug?

[Jason House]

My friend using a mac has had severe issues getting my project (recently ported to Tango) to run on his machine.

Looking at debug output and doing some tests, it appears that Stdout is not flushing.  

Typical offending code:
auto outStream = new Print!(char)(new Layout!(char),Stdout);
outStream.formatln("= {}\n", valueToReturn); // adds extra \n and flushes


Sometimes I get a non-response too, but restarting the program usually fixes it.  It appears that on the mac this is not the case.  Any ideas what could be wrong?  I do not know which version of tango my friend is using.  I think I'm using Tango 0.99 rc1 with dmd 1.020.