"Can't bless non-reference" error, bug or not?

I am working on something using JPL from Perl side and have got
some errors with the bless function in "AutoLoader.pm":

     >>>Can't bless non-reference value at AutoLoader.pm line 237.

The line 237 of Autoloader is:
	bless $self->$callmethod($mid, \@_), $blesspack;

I have solved my problem by adding a line to check the reference:

	if ( ref $self->$callmethod($mid, \@_)) {
    		bless $self->$callmethod($mid, \@_), $blesspack;
	}
 
Brian, what is your opinion?
 
Thanks,
Chunyan Wei