I can only guess you have an old version of DBD::ODBC - what version have you got? This self contained example works for me:

use strict;
use warnings;
use DBI;
use Data::Dumper;

my $h = DBI->connect("dbi:ODBC:xxx","xxx","xxx", {RaiseError => 1, Pri
+ntError => 0});

eval {
    $h->do(q/drop table mje/);
};

$h->do(q/create table mje (a int)/);
$h->do(q/insert into mje values(1)/);

my $s = $h->prepare(q/select * from mje where a = ?/);
eval {
    $s->execute('fred');
};
if ($@) {
    print "$@";
    print Dumper($s->{ParamValues});
}
# outputs
# DBD::ODBC::st execute failed: [unixODBC][Easysoft][SQL Server Driver
+ #11.0][SQL Server]Invalid character value for cast specification (SQ
+L-22018) #at paramvalues.pl line 17.
#$VAR1 = {
#          '1' => 'fred'
#        };
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