Unlocked iPhone but won't let me call or sms. 3g works only

[ninexz]

Hi guys, first post here. I have tried running a search but have not seem to come across anything.

Anyway I have an iphone 3g running on 3.0 It is jailbroken and network unlocked. I believe the guy who unlocked it for me also spoofed me a new IMEI number, but I am not certain. I am in Australia and with the Optus network. The phone was originally locked to telstra.

The huge issue I am having is that the iphone works half the time, the other half, it doesn't.
It will randomly stop working and whenever I make a call it redirects me to my service provider and gives me the message "This handset has been blocked from the optus mobile network..." However, the 3G and edge compatibilities still work, and still use download data off my sim.
The only way to fix this is to take my sim card out, put it in another phone, make a phone call, then put the sim back into the iphone and it will work for another 5 hours or so, but then screw up again.

I will be VERY greatful if anyone can give me insight into why this is happening or help me fix it.

Thanks alot!

[kill2bill]

I think that there is a problem with the sim. but this is just my opinion.

[drmias]

It could be deactivated by the official carrier.

[ninexz]

I just checked the IMEI number (dialed *#06#) and it tells me that it IS infact being blocked by telstra...

If this is the case, I still don't understand why it works half the time, and doesn't for the other half

[drmias]

maybe the next carrier unlock tool will help you.

[soulthoughts]

It could be blacklisted or the IMEI that was spoofed could be blacklisted if in fact it was spoofed.

[Cer0]

Only the 2g was able to change the IMEI. Should have asked him in the first place why he would need to spoof the IMEI.