I am not sure if you guys are still having problems. If you are you may want to check what equipment you are trying to train up to. These routers use newer chipsets which sometimes are not compatible with the older equipment used by ISPs. Do a show int to see what hardware the card is using and cross reference the info along with the model of the router to see if your ISP is using an equipment that is compatible. You will however need some info from the ISP, sorrrrry....
Cisco ISR and ISR G2 xDSL Interoperability FAQ http://www.cisco.com/c/en/us/products/collateral/routers/888-integrated-services-router-isr/qa_c67-532551.html
Under your Dialer int you may want to configure both CHAP and PAP authentication methods to make sure you don't run into authentication problems.
ppp authentication pap chap callin ppp chap hostname hi ppp chap password bye