Your software is REALLY old, you need to update it. I have read somewhere that the older software does not work properly on the new hardware. If you just received this from Sprint, I am sure it did not come with this software. I assume you rooted it, then flashed this older software.
You can get a newer RUU from
Shipped ROMs , click the android, then SUPERSONIC.
Lets compare software versions :
YOU ME
Firmware version: 2.1-update1 ???
Baseband version: 1.39.00.05.31 Baseband version: 2.15.00.0808
Kernel version: 2.6.29-a2443432 Kernel version: 2.6.35.10-g13578ee
Build number: 1.32.651.6 CL171253 Build number: 4.54.651.6 CL134969
Software number: 1.32.651.6 Software number: 4.54.651.1
Browser version: WebKit 3.1 Browser version: WebKit 533.1
PRI version: 1.90_003 PRI version: 2.15_003
PRL version: 60683 PRL version: 60681
As you can see, you are pretty far out of date. But at least you updated you PRL?