TC hangs all the time running my command line build (windows)

I would like to run a build on windows using a version of nant that is checked into my source tree, for a number of reasons.

the build works perfectly from a desktop, and is kicked off with a batch file (build.bat)

however, when running on TC, the bulid hangs 9 times out of 10, after the batch file exits.

i have tried various combinations of

build.bat
cmd.exe /c build.bat
cmd.exe build.bat

but the all demonstrate the same behaviour

this is 4.5.4.9071
please if anybody has any ideas....


thanks!