Special characters in XML barcode content

Hello,

I made a barcoded form with a custom script that creates a custom XML as barcode content.

The decoding happens well when the user write plain text in the text fields, but whenever it inputs some special characters (for XML syntax), like ",<,>,=,etc... the content of barcode it is decoded as:

<barcode>

<!CDATA[... true content ...]>

</barcode>

how can I handle this situation?

I have to handle what the user writes or I have to change the decode activity?

Thank you very much for your support!

Fabio