If your with sprint,, here are a few address I found that may help... you can go to the page and there is some info on doing this,, granted it is for an aircard,, but its the same same,, so should carry over just fine for the mogul...
here is the website
http://www.evdoinfo.com/content/view/1960/63/
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68.28.49.76 San Jose, CA Area 1
68.28.49.77 San Jose, CA Area 1
68.28.57.76 Anaheim, CA Area 1
68.28.57.77 San Jose, CA Area 7 (possible DNS config issue, likely Anaheim)
68.28.81.76 Kansas City, KS Area 2
68.28.81.77 Kansas City, KS Area 2
(could be Omaha)
68.28.89.76 Kansas City, MO Area 2
68.28.89.77 Kansas City, MO Area 2
68.28.113.76 Pennsauken, NJ Area 3
68.28.113.77 Pennsauken, NJ Area 3
68.28.121.76 New York, NY Area 3
68.28.121.77 New York, NY Area 3
68.28.145.76 Chicago, IL Area 4
68.28.145.77 Chicago, IL Area 4
68.28.153.76 Roachdale, IN Area 4
68.28.153.77 Roachdale, IN Area 4
68.28.177.76 Fort Worth, TX Area 7
68.28.177.77 Kansas City, KS Area 5 (possible DNS config issue, likely Ft. Worth)
68.28.185.76 Atlanta, GA Area 5
68.28.185.77 Atlanta, GA Area 5
(speedtest.net says in Houston)
68.28.241.76 Relay, MD Area 7
68.28.241.77 Relay, MD Area 7
(speedtest.net says in Florida)
68.28.249.76 Atlanta, GA Area 7
68.28.249.77 Atlanta, GA Area 7