I'm experiencing a similar problem with v1.3.8. Yesterday I installed security_patchv138_20090619 followed by the RFQ shipping and payment module. I also have the backup_MYSQL_admin_plugin and super_orders_20_rev47 installed (both installed some weeks ago). Everything appeared to be working until I tried to configure the rfq plug-in in the shipping module. The error message appearing on my admin shipping module page (which is now minus some of it's original content as described by V_linck) is:

Fatal error: Cannot use object of type queryFactoryResult as array in /var/www/neshop/includes/modules/shipping/rfq.php on line 43

Any help would be appreciated. I'd love to be able to use this module. It would be an extremely helpful addition.

TIA