Fix t/inflate/datetime.t warning on older perls

diff --git a/t/inflate/datetime.t b/t/inflate/datetime.t
index fe35c0e..14a2ce0 100644 (file)
--- a/t/inflate/datetime.t
+++ b/t/inflate/datetime.t
@@ -8,7 +8,7 @@ use lib qw(t/lib);
 use DBICTest;
 
 # so user's env doesn't screw us
-undef $ENV{DBIC_DT_SEARCH_OK};
+delete $ENV{DBIC_DT_SEARCH_OK};
 
 my $schema = DBICTest->init_schema();