What is the best way to escape characters for xsl-fo code generated by form widgets?

[Jacopo Cappellato]

Hi all,

I'd like to escape the special characters (not allowed in xsl-fo 
template) from the data formatted by the form widget (see 
org.ofbiz.widget.fo.FoFormRenderer.makeBlockString(...)).
Since I'm a lazy person and I don't want to reinvent the wheel, my 
question is: what is the best way to escape these characters? Is there a 
method that I can use for this?

Thanks,

Jacopo