I just fixed mine - it had exactly the same problem.
First, though, check it's not within the Bosch TWO year guarantee; if it is, they'll either fix or replace it.
If it's not under guarantee then the problem is probably the rubber tubing that connects the external steam tube to the hotplate. You'll need to dismantle the iron. Mine had split right next to the spring clip that holds it on. I shortened it, clipped it back on and all is now well.
Neil Martin, February 2013
