psi: want ssl but error message says "plugin not found"

[Jeff Co]

hello,
i have just installed psi 0.9.3 from synaptic. In AccountProperties/Connection Tab, I tried putting a checkmark on the Option that says "Use SSL encryption (to server)" but I get an error message that says "
Cannot enable SSL/TLS. Plugin not found."

What's going on? Just to let you know I already have libssl0.9.7 installed.

jc