weird Runtime.exec() problem

I need to run a command, basically:

Runtime rt = Runtime.getRuntime();

command = "dostuff -a blah -d \"blah blah\"";

Process p = rt.exec(command);
p.waitFor();

the second argument is the problem, for some reason the application treats the quoted argument as two separate ones and comlains that 'blah"' does not start with a '-'

if I echo this exact command and then copy and paste it from the shell, it works fine

any suggestions?