Call redirection onto the same PRI

I have my second massive problem. I can transfer call from one pri(g0) to another by simple:

exten => mynumber,1,Dial(DAHDI/g1/number)

but can’t redirect all to the same pri trunk g0 thi way. If I want to do this It work only with setting callerid first, before dial. Is it nesessary?

Accepting call from ‘60XXXXXX’ to ‘61XXXXXX’ on channel 0/2, span 1
– Executing [61XXXXXX@incoming:1] Dial(“DAHDI/i1/60XXXXXX-e0e”, “DAHDI/g0/50XXXXXX”) in new stack
– Requested transfer capability: 0x00 - SPEECH
– Called DAHDI/g0/50XXXXXX
– Span 1: Channel 0/3 got hangup, cause 21
– DAHDI/i1/50XXXXXX-e0f is circuit-busy
– Hungup ‘DAHDI/i1/50XXXXXX-e0f’
== Everyone is busy/congested at this time (1:0/1/0)
– Executing [61XXXXXX@incoming:2] Hangup(“DAHDI/i1/60XXXXXX-e0e”, “”) in new stack
== Spawn extension (incoming, 61XXXXXX, 2) exited non-zero on ‘DAHDI/i1/60XXXXXX-e0e’
– Hungup ‘DAHDI/i1/60XXXXXX-e0e’
– Hungup ‘IAX2/565-12281’
== Spawn extension (incoming, 61XXXXXX, 1) exited non-zero on ‘DAHDI/i1/438437961-e0d’
– Hungup ‘DAHDI/i1/438437961-e0d’