os.execvp()'ing an ssh command on windows

[Kevin Smith]

I have a tool that invokes a command on a remote machine using ssh 
(cygwin) on Windows.  Typing the command at a command prompt works 
fine.  I get prompted to verify the host and asked for a password.  If 
I try the same command under python using an os.execvp(), things get 
screwy.  I get prompted to verify the host and for a password, but I 
can't type them in.  It's as if the command prompt has taken control 
again.  Is there any way to exec an interactive program such as ssh?

Kevin Smith