[ic] Perl / Session question

[interchange at thedesignpeople.com]

Could someone knowledgable in perl be kind enough to help me out here.

I have discovered that this works to manually set the discount:
   $Session->{discount} = ({
                     'code1' => '199',
                     'code2' => '199',
                     'code3' => '199'
			});

I thought the following would have the same effect but does not work:
# create empty array
@arrayval = ();
# create a hash
$hashval = {
           'code1' => '199',
           'code2' => '199',
           'code3' => '199'
           };
# put the hash into an array
push @arrayval, $hashval;

$Session->{discount} = @arrayval;

The script dies with the following error:
Runtime error: Can't use string ("1") as a HASH ref while "strict refs" 
in use at /www/interchange/interchange-5/lib/Vend/Interpolate.pm line 5151.

I'm not sure what this error means.
Can someone please explain what I'm doing wrong?

Thanks

Mike Kang