You can now get the latest version of NuSOAP via CVS at sourceforge.net. I build, test and update nusoap.php every time I commit, so you can get all classes at once, or download just the individual class you want to update:
http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/nusoap/lib/.
Changes:
- added support for http encoding w/ gzip and deflate. only works for receiving, not sending, and requires Zlib extension compiled into php.
- many bugfixes and performance enhancementsLink