This is FAQ.
How did you output the value in BIRT:
Is it with a Data item or with a DymamicText item (or RotatedText item)?
For Data, BIRT interpretes the values as plain text.
For DynamicText and RotatedText, BIRT's default is to interprete the value as HTML. And your value is invalid HTML! So, just change the "Content Type" property from HTML to Plain.