OK, it's pretty clear that I did something wrong in setting up the externalDB.  I pretty much pasted the example from the admin guide into Config.pm and edited it.  It's at least partially working because I can see the customers and create tickets for them.  In addition to the weird thing that happens when creating tickets (which I posted about separately), I also get an error when I load customer.pl.  I pasted it below.

I must be overlooking something fundamental.

Error: Need CustomerID!!!

Comment:

Traceback:

ERROR: OTRS-CGI-10 Perl: 5.14.2 OS: linux Time: Fri Jun  7 14:28:22 2013

 Message: Need CustomerID!!!

 Traceback (1654): 
   Module: Kernel::Output::HTML::Layout::CustomerError (v1.381.2.10) Line: 3653
   Module: Kernel::Modules::CustomerTicketOverview::Run (v1.4.2.1) Line: 68
   Module: Kernel::System::Web::InterfaceCustomer::Run (v1.63) Line: 998
   Module: ModPerl::ROOT::ModPerl::Registry::usr_share_otrs_bin_cgi_2dbin_customer_2epl::handler (unknown version) Line: 46
   Module: (eval) (v1.44) Line: 204
   Module: ModPerl::RegistryCooker::run (v1.44) Line: 204
   Module: ModPerl::RegistryCooker::default_handler (v1.44) Line: 170
   Module: ModPerl::Registry::handler (v1.99) Line: 31