DBD::Pg installation difficulty during make test

I am attempting to install DBD::Pg version 1.13, and I'm using postgresql
7.2.2, Perl 5.8.0, on a Mandrake 9.0 release.  The first two steps of the
installation went smoothly (i.e. perl Makefile.PL, and make), but when I
try to make test I get many failures of the DBI->connect(...) method,
specifically:

"DBI->connect(dbase=MYDBASE) failed: FATAL 1: IDENT authentication failed
 for user "MYUSER"."

I have the configuration file set up NOT to use IDENT authentication:

local all trust
host all 127.0.0.1 255.255.255.255 trust

and I know that MYDBASE and MYUSER are valid because I can access the
database manually (i.e. psql MYDBASE MYUSER) without a problem (although,
if while within MYDBASE, I try to use the \connect command to access
another database as another user, this fails).  Looking in the logfile, I
just see the FATAL 1 error message, with little to no additional
information.  Could someone offer some suggestions to help me figure out
why DBI->connect(...) isn't working?  Oh, and I'm a super newbie, so please
talk down to me.  :-)

Don