You shouldn't need to SSH anything.
The APN settings are in your menu: General> Network> Cellular Data Network>
You will then need to complete the APN, Username and Password details which you might be able to find via a google search...
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OK, so I got the below info for you:-
Fields not specified should be blank.
GPRS Web Session:
Homepage:
http://172.23.1.135:8080/cellularone.wml
Service Type 1: WAP
Gatewap IP 1: 172.23.1.252
Port 1: 9201
Service Type 2: WAP
Gateway IP 2: 172.23.1.252
Port 2: 9201
Timeout: 15 minutes
GPRS APN: cellular1wap
So, as
dhkosta posted you will only need to complete the APN field.