Type change in perl between 8.1 and 8.4

I'm upgrading a debian server from etch to squeeze, so Postgres 8.1 to 8.4.

One of the perl scripts is doing odd things, and it has been noted that for example
in perl, field client on squeeze is 'client' => 1246, client on etch is 'client' => '1246' - so one is an int, one text. This breaks the perl. Has anything changed in the Postgres libraries that could cause this, or is it a Perl issue?

Thanks.