Call transfer problem

I need to be able to transfer te call from extension A to extension B. I can do it suscessfully if A waits until B answers and then hangs up, but, if A hangs up BEFORE B answer, the call si disconnected. I need fo B to continue ringing even if A hangs up before he answers, and that the call s no lost. I am using the DIAL() applicaciont o make the calls. here is my context:
exten => _1xx,1,SetCallerID(${CALLERIDNUM:3})
exten => _x.,1,SetCallerID(6004400)
exten => 101,2,Dial(SIP/002101,30)
exten => 102,2,Dial(SIP/002102,30)
exten => 103,2,Dial(SIP/002103,30)
exten => 107,2,Dial(SIP/002107,30)
exten => 108,2,Dial(SIP/002108,30)
exten => 109,2,Dial(SIP/002109,30)
exten => 111,2,Dial(SIP/002111,30)
exten => 112,2,Dial(SIP/002112,30)
exten => 113,2,Dial(SIP/002113,30)
exten => 115,2,Dial(SIP/002115,30)
exten => 116,2,Dial(SIP/002116,30)
exten => 117,2,Dial(SIP/002117,30)
exten => 118,2,Dial(SIP/002118,30)
exten => 119,2,Dial(SIP/002119,30)
exten => 120,2,Dial(SIP/002120,30)
exten => _xxx,3,Hangup()
exten => _xxx,103,Playback(custom/extocupada)
exten => _xxx,104,Hangup()

Thanks in advance.

When calling exten => 101,2,Dial(SIP/002101,30) add a lowercase “t” to it.

Example:

exten => 101,2,Dial(SIP/002101,30,t)
exten => 102,2,Dial(SIP/002102,30,t)
exten => 103,2,Dial(SIP/002103,30,t)
exten => 107,2,Dial(SIP/002107,30,t)
exten => 108,2,Dial(SIP/002108,30,t)

etc…etc…

then in features.conf what you have defined for blindxfer

example:
blindxfer => #4

Then if SIP A gets the call… they can press #4 and enter the ext they want to transfer to ( SIP B). SIP A is immediately removed from the call.

Thanks, that works, great, now, is there any way to do it with the FLASH key instead of #, my user sare accostumed to use the flash key for call transfer.

Thanks again

Aquiles