Here is a handy dandy reg editor for ppc. Note you must run this program from your pc and connect to your ppc through usb connection.
************************************************** ******
Internet sharing giving you the sprint
Error code 67? Well thats cause you been a bad little girl. Get down on your knees and do the following:
note this may or may not work on unofficial roms.
Here's what to do for windows mobile 6.1.
1.) Install CeRegistryEditor on your
PC.
2.) Connect your ppc to your computer and allow active sync to connect.
3.) Opened CeRegistryEditor, click on connection and then click on connect. Once connected, go to tools and click on
unlock registry.
4.) Go to HKEY_LOCAL_MACHINE\Comm\Internetsharing and double click on isext.dll and rename it to isext_disable.dll (don't delete it, you might need this file one day

)
5.) Do a soft reset and enjoy! =D>
Here's what to do for windows mobile 6
1.) Install CeRegistryEditor on your
PC.
2.) Connect your ppc to your computer and allow active sync to connect.
3.) Opened CeRegistryEditor, click on connection and then click on connect. Once connected, go to tools and click on
unlock registry.
4.) Go to HKEY_LOCAL_MACHINE\Comm\Internetsharing and double click on rilphone.dll and rename it to rilphone_disable.dll (don't delete it, you might need this file one day

)
5.) Do a soft reset and enjoy! =D>