When I did my Master's Thesis Work, I searched for compact XML parsers for an embedded system. I found a bunch of open-source solutions in ANSI-C which should compile without any problems on Amiga. Search for XML at sourceforge.net...
There seems to be some XML solutions for Amiga too:
http://wuarchive.wustl.edu/~aminet/aminet.cgi?string=xml
