I’ve noticed that all attribute declarations in xapplication.tld don’t allow me to use runtime expressions. Is there any reason for that? Can I safely turn them on?
I don’t see any reason why you should no use runtime expressions.
However have to switch the JSP standard from 1.1 to 1.2
<!DOCTYPE taglib PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.2//EN" "http://java.sun.com/dtd/web-jsptaglibrary_1_2.dtd">
As I read in the DTD you specified it will be also necessary to add tag true for each attribute declaration in xapplication.tld file. The default is false. So it’s great to hear that it will work!