Web Services Tool Kit for Mobile Devices provides tools and run-time environments that allow development of applications that use Web Services on small mobile devices. This tool kit’s JavaTM Web service run-time environment is supported on PoctketPC, Palm, and BlackBerry. The C Web service run-time environment is supported on the Palm and Symbian. What’s new in Version 2.0: Preview implementation of the JSR 172 Version 0.7 specification; C-based Web services now supported on Palm OS 5.0 and Symbian OS 6.0, 6.1; Java-based Web services now run on Palm OS 3.5.
Remember, there are also libraries available in J2ME for SOAP, XML-RPC, UDDI, XML parsing and more at Enhydra.org.