$ perl -e'
>    sub method {}
>    my $o = bless({});
>    $o->method();  # Ok
>    $o = "$o";
>    $o->method();
> '
Can't locate object method "method" via package "main=HASH(0x814ec28)" (perhaps you forgot to load "main=HASH(0x814ec28)"?) at -e line 6.