dial-peer authenticaton in ios 12.3?

Hello everybody, Is there a good person who could try to remember how to configure authentication in dial-peer on IOS (tm) MC3810 Software (MC3810-A2ISV5-M), Version 12.3(13), RELEASE SOFTWARE (fc2)? dial-peer voice 1 pots authentication username someuser password somepassword does not seem to be any help as it points an error on "authentication" keyword. Is there anything I could try to do about this before I through it out from my balcony? Thank you. -- With best regards, Gregory Edigarov