[Zope] unicode support

I am using Zope 2.9 connected to a Posgres DB via psycopg. My database encoding is UTF8. I am getting the following error when users try to insert text in the database containing £ signs: ERROR: invalid byte sequence for encoding "UTF8": 0xa3 This is due to the encoding of a £ sign in the text being sent to the DB. My question then is how do I make sure that all encodings submiitted from forms are in the correct UTF8 format? Regards Garry