Have you tried this?
Start client-initiated IOTA- In phone dialer, tap Tools, Options and then Services.
- In Services, tap Internet, and then Get Settings.
- Tap Start.
Also, here are the IOTA related reg settings from the 2.16 ROM
[HKEY_CURRENT_USER\ControlPanel\PhoneExtendFunction \IOTA\Phone\Default]
"Wdp"="c4000050441c1f01"
"Homepage"="vision.sprintpcs.com"
"PrlStorage"="16384"
"PsaVersion"="01.00"
"BootUrl"="http://hcmci.iota.spcsdns.net:8080/ciip"
"DomainTrusted"="https:.iota.spcsdns.net"
"NaiUrl"="http://hcmci.iota.spcsdns.net:8080/cisp"
"OEM"="High Tech Computer"
"Model"="PPC6800"
"SwVersion"="M7500-SACAAAAAM-4070"
[HKEY_CURRENT_USER\ControlPanel\PhoneExtendFunction \IOTA\Phone]
"Wdp"="c4000050441c1f01"
"Homepage"="vision.sprintpcs.com"
"PrlStorage"="16384"
"PsaVersion"="01.00"
"BootUrl"="http://hcmci.iota.spcsdns.net:8080/ciip"
"DomainTrusted"="https:.iota.spcsdns.net"
"NaiUrl"="http://hcmci.iota.spcsdns.net:8080/cisp"
"OEM"="High Tech Computer"
"Model"="PPC6800"
"SwVersion"="M7500-SACAAAAAM-4070"
[HKEY_CURRENT_USER\ControlPanel\PhoneExtendFunction \IOTA\SIP]
"Edgeproxy0"="xx.xx.xx.xx"
"Edgeproxy1"="yy.yy.yy.yy"
"DataExchange0"="http://sip.dataexchange0.com"
"DataExchange1"="http://sip.dataexchange1.com"
"DataGateway0"="http://sip.datagateway0.com"
"DataGateway1"="http://sip.datagateway1.com"
"ConfigServer0"="http://sip.configserver0.com"
"ConfigServer1"="http://sip.configserver1.com"
"IMStore0"="http://sip.IMstore0.com"
"IMstore1"="http://sip.IMstore1.com"
"RetryTimer0"="1000"
"RetryTimer1"="4000"
"RetryCount0"="5"
"RetryCount1"="0"
[HKEY_LOCAL_MACHINE\SOFTWARE\OEM\MASD]
"IOTA"="20070427"