just enter your *curent* IP..
you can change it within your account settings, OR request it to be changed via support ticket.
so long as it is not changing *that* often, i'm sure..
*most* Dynamic IP's via CABLE Provider do not change that often, ive had mine for over 5 years.
for example..
although, if you are on a Satellite hookup, you may have to use a Proxy such as DynDNS.com or no-ip.com
That should solve your problem.
HTH.
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