UTF-8 question

Hello,
I have implemented a java application which extracts information from an iso-8859-1 encoded XML file using the JDOM
parserand feeds it into a postgresql database. Everything is running on linux. I am using Postgres 7.1.3 and
jdbc7.0-1.1.Now I would like to do the same thing with UTF-8 encoded XML files. 
Since I have no experience with unicode and utf-8 I would like to know whether I have to expect difficulties at the
JDBCand Postgres side of the thing (my Postgres database is already configured for unicode). 
I would also like to know a simple way to feed some unicode characters into a Postgres database, get them out again,
anddisplay them on the screen just for testing purposes. I tried it with pgaccess but it doesn't seem to be unicode
enabled.
Many thanks for your help.
Anton

// Anton Güntsch
// Botanic Garden and Botanical Museum Berlin Dahlem,
// Dept. of Biodiversity Informatics
// Königin-Luise-Str. 6-8, D-14191 Berlin
// Phone: +49-30 / 83850-166   Fax: +49-30 / 841729-55
// Email: a.guentsch@bgbm.org
// URL: http://www.bgbm.org/guentsch/