I'm also getting this exact same error.
PHP Built on: Windows NT BLUEPEARL2 5.1 build 2600
Database Version: 5.0.45-community-nt
Database Collation: utf8_general_ci
PHP Version: 5.2.4
Web Server: Apache/2.2.4 (Win32) PHP/5.2.4
Web Server to PHP interface: apache2handler
Joomla! Version: Joomla! 1.5.3 Production/Stable [ Vahi ] 22-April-2008 22:00 GMT
with Community Builder 1.1
Any help appreciated, any thoughts appreciated,
Thanks,
KWL