[default]
[from-internal]
exten = 6002,1,Dial(PJSIP/BOB,,b(section-setheaders^setheaders^1))

[section-setheaders]
exten = setheaders,1,Set(PJSIP_HEADER(add,P-Asserted-Identity)=sip:01234456789@domain.local)
 same = n,Return()