Maybe a good idea would be using the sort SUBNAME LIST subroutine. With SUBNAME you specify a subroutine that will take care of comparing two elements and it will return depends on the outcome of the comparison.
The Camel Book states the following sub for sorting numerically:

sub numeric {$a <=> $b}

The <=> operator will take care of everything! Of course you will need to change the above sub to fit exactly your needs, but that should be a piece of cake. :-) If not dare to ask again :-)

Bye,
C-Keen