Put this in right after use strict: 
use vars qw($opt_h $opt_d $opt_t);

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UDPDATE:
jerones suggested me to point you to our and a great discussion on how it works: Why is 'our' good?.

Jeff 

R-R-R--R-R-R--R-R-R--R-R-R--R-R-R--
L-L--L-L--L-L--L-L--L-L--L-L--L-L--

In reply to (jeffa) Re: how do i use module vars while using use strict; ? by jeffa
in thread how do i use module vars while using use strict; ? by L8on

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