[oe] Question on writing perl lib .bb files

[J. L.]

I am trying to add a few more perl libs into my build that dont exist
and I have seen some that have dependences and others that dont. So I
wrote one for Net::Whois::ARIN and tried without what CPAN says is the
dependencies and it built correctly with no errors I installed the
.ipk and went to try the build of a program I wanted to try on my
overo and it no longer complains about it missing that. But why do
some perl lib .bb use depends and not even all the depends that cpan
lists and some list none even though according to CPAN they need them?
I will post the .bb I wrote as well, thanks for any info on the
correct way to do this as not sure if what I did is enough to properly
get the lib for perl built

DESCRIPTION = "Net::Whois::ARIN   	whois arin "
SECTION = "libs"
LICENSE = "Perl"
PR = "r1"

DEPENDS += "libtest-mockmodule-perl scalar-util-perl libtest-exception-perl \
	    test-harness-perl test-more-perl libsub-uplevel-perl \
	    libmodule-build-perl carp-perl universal-isa-perl \
	    universal-can-perl io-socket-inet-perl "

SRC_URI = "http://search.cpan.org/CPAN/authors/id/T/TC/TCAINE/Net-Whois-ARIN-${PV}.tar.gz"

S = "${WORKDIR}/Net-Whois-ARIN-${PV}"

inherit cpan

BBCLASSEXTEND="native"

SRC_URI[md5sum] = "a5aee39187c6272acd2a77e30847fdef"
SRC_URI[sha256sum] =
"d47a6720ff265674cbd918d866c73221be9916d81e1c30ccdb0d49e6b45110e8"