curl response

In a shell I call:

/usr/bin/curl https://api.stripe.com/v1/tokens  -u 23473248756384765 -d "card[number]=4242424242424242" -d "card[exp_month]=12" -d "card[exp_year]=2015" -d "card[cvc]=123"

The remote host requires me to enter a password at that point by returning:

Enter host password for user:

All i need to do is send a CR because the password has already been established.

How can I use the shell to send a second line?

Create a Shell subclass, put it in Interactive mode, and raise an Event when it asks for the password.