You can check the device_os capability to look for iPhoneOS, Android, etc, or check that xhtml_support_level >= 4, this indicates full web browser functionality including AJAX (http://wurfl.sourceforge.net/help_doc.php#markup).
Thanks,
Steve Kamerman Tera-WURFL Author COO of ScientiaMobile
IMPORTANT ANNOUNCEMENT! Tera-WURFL and WURFL have joined forces! We have launched ScientiaMobile to provide commercial support for our device detection solutions.