[asterisk-ss7] ewsd problems

[chamo]

hello,
i have some problems with ss7 interconnect , with EWSD

first, when i do outbound call to concrete channel , call is made, and
it works no ok

exten => _9.,1,Dial(DAHDI/6/${EXTEN:1})
exten => _9.,n,Hangup

but if i dial without channel id, i get an error

exten => _8.,1,Dial(DAHDI/${EXTEN:1})
exten => _8.,n,Hangup

    -- Executing [30432661123 at default:1] Dial("SIP/0485500002-b7da93c8",
"DAHDI/0432661123") in new stack
[May 19 15:04:27] WARNING[15577]: app_dial.c:1715 dial_exec_full: Unable
to create channel of type 'DAHDI' (cause 0 - Unknown)
  == Everyone is busy/congested at this time (1:0/0/1)

so how asterisk choose, which channel to use, problem may be with my
configuration, when my signaling is on channel 1, and asterisk is trying
to make a call on this channel
can i explicitly say to asterisk to jump first channel ? , actually it
should start with 3rd, because of lower Point Code than Adj. Point Code
(cicbeginswith = 2 in my config)

my second problem is with dial-in from ss7 to asterisk

my dialplan
[ss7]
exten => _!,1,Answer
exten => _!,n,Wait(1)
exten => _!,n,Dial(SIP/0485500002)
exten => _!,n,Hangup(34)

when iam not call with overlap it works good, with overlap dialing,
asterisk send Answer immediately , and this is a problem
i tried
exten => _4855XXXXX.,1,Answer
exten => _4855XXXXX.,n,Wait(1)
exten => _4855XXXXX.,n,Dial(SIP/0485500002)
exten => _4855XXXXX.,n,Hangup(34)

but i allways get unallocated number

this also works, but with overlap i get answer after four number and
therefor i can't pass the tests
exten => _2855.,1,Answer
exten => _2855.,n,Wait(1)
exten => _2855.,n,Dial(SIP/0485500002)
exten => _2855.,n,Hangup(34)

thanks for any help

regards

peter