I had a hell of a time getting everything to stick with PST once you get your internet working go here
;[Only registered and activated users can see links. ]
and follow step 10 in qpst workshot Be Sure noto to read from phone. but if you enter all that correctly then write. You'll be sending in seconds. Figured it would help for all the folks out there still using cdma 2.7
Also of course cover the basics make sure that it's set to sip only and such but tI've tried this method and it's worked lots of times.