I had same problem and the decision is very simple,
It's enough this
<!DOCTYPE tiles-definitions PUBLIC
"-//Apache Software Foundation//DTD Tiles Configuration 1.3//EN"
and then to put the dtd file on the directory from witch is started the JBoss and on CLASSPATH. I start my JBoss complexy and for this purpose I put dtd files on the starting folder of JBoss, but on CLASSPATH is mandatory. The above script work i use this way. Good luck!