typography class & and &

[eluser]Flying Fish[/eluser]
I'm using codeigniter for an app that generates xml files which are then imported into Adobe inDesign.

Users input data into form inputs, the data is stored in a db, and an administrator can log into the back end and download xml files.

Trouble is, inDesign chokes on the '&' character when it sits in the text of the xml tags.

inDesign does however correctly handle the html &

I was wondering if I should write a function that does a string replace on '&' before each xml file is created, or if there was a more fancy codeigniter way of doing it with the typography class.