It sounds like Perl would be a great fit for your job. Perl is a great choice for building database-driven websites and has good support for XML and Unicode.

Since you don't know it yet you'll need to give yourself time to get up to speed. I suggest you pick up a copy of "Learning Perl" from O'Reilly and find some small jobs to do while you learn. When you're done with that proceed to "CGI Progamming with Perl," "Programming the Perl DBI" and "Network Programming with Perl." These last three contain critical information you'll need to build your application using the best Perl techniques.

-sam