Interner Hilfetext zu dieser Applikation in Asterisk 1.4: 

  -= Info about application 'Dial' =- 

[Synopsis]
Place a call and connect to the current channel

[Description]
  Dial(Technology/resource[&Tech2/resource2...][|timeout][|options][|URL
]):
This application will place calls to one or more specified channels. As 
soon
as one of the requested channels answers, the originating channel will b
e
answered, if it has not already been answered. These two channels will t
hen
be active in a bridged call. All other channels that were requested will
 then
be hung up.
  Unless there is a timeout specified, the Dial application will wait
indefinitely until one of the called channels answers, the user hangs up
, or
if all of the called channels are busy or unavailable. Dialplan executin
g will
continue if no requested channels can be called, or if the timeout expir
es.

  This application sets the following channel variables upon completion:
    DIALEDTIME   - This is the time from dialing a channel until when it
                   is disconnected.
    ANSWEREDTIME - This is the amount of time for actual call.
    DIALSTATUS   - This is the status of the call:
                   CHANUNAVAIL | CONGESTION | NOANSWER | BUSY | ANSWER |
 CANCEL
                   DONTCALL | TORTURE
  For the Privacy and Screening Modes, the DIALSTATUS variable will be s
et to
DONTCALL if the called party chooses to send the calling party to the 'G
o Away'
script. The DIALSTATUS variable will be set to TORTURE if the called par
ty
wants to send the caller to the 'torture' script.
  This application will report normal termination if the originating cha
nnel
hangs up, or if the call is bridged and either of the parties in the bri
dge
ends the call.
  The optional URL will be sent to the called party if the channel suppo
rts it.
  If the OUTBOUND_GROUP variable is set, all peer channels created by th
is
application will be put into that group (as in Set(GROUP()=...).

  Options:
    A(x) - Play an announcement to the called party, using 'x' as the fi
le.
    C    - Reset the CDR for this call.
    d    - Allow the calling user to dial a 1 digit extension while wait
ing for
           a call to be answered. Exit to that extension if it exists in
 the
           current context, or the context defined in the EXITCONTEXT va
riable,
           if it exists.
    D([called][:calling]) - Send the specified DTMF strings *after* the 
called
           party has answered, but before the call gets bridged. The 'ca
lled'
           DTMF string is sent to the called party, and the 'calling' DT
MF
           string is sent to the calling party. Both parameters can be u
sed
           alone.
    f    - Force the callerid of the *calling* channel to be set as the
           extension associated with the channel using a dialplan 'hint'
.
           For example, some PSTNs do not allow CallerID to be set to an
ything
           other than the number assigned to the caller.
    g    - Proceed with dialplan execution at the current extension if t
he
           destination channel hangs up.
    G(context^exten^pri) - If the call is answered, transfer the calling
 party to
           the specified priority and the called party to the specified 
priority+1.
           Optionally, an extension, or extension and context may be spe
cified. 
           Otherwise, the current extension is used. You cannot use any 
additional
           action post answer options in conjunction with this option.
    h    - Allow the called party to hang up by sending the '*' DTMF dig
it.
    H    - Allow the calling party to hang up by hitting the '*' DTMF di
git.
    i    - Asterisk will ignore any forwarding requests it may receive o
n this
           dial attempt.
    j    - Jump to priority n+101 if all of the requested channels were 
busy.
    L(x[:y][:z]) - Limit the call to 'x' ms. Play a warning when 'y' ms 
are
           left. Repeat the warning every 'z' ms. The following special
           variables can be used with this option:
           * LIMIT_PLAYAUDIO_CALLER   yes|no (default yes)
                                      Play sounds to the caller.
           * LIMIT_PLAYAUDIO_CALLEE   yes|no
                                      Play sounds to the callee.
           * LIMIT_TIMEOUT_FILE       File to play when time is up.
           * LIMIT_CONNECT_FILE       File to play when call begins.
           * LIMIT_WARNING_FILE       File to play as warning if 'y' is 
defined.
                                      The default is to say the time rem
aining.
    m([class]) - Provide hold music to the calling party until a request
ed
           channel answers. A specific MusicOnHold class can be
           specified.
    M(x[^arg]) - Execute the Macro for the *called* channel before conne
cting
           to the calling channel. Arguments can be specified to the Mac
ro
           using '^' as a delimeter. The Macro can set the variable
           MACRO_RESULT to specify the following actions after the Macro
 is
           finished executing.
           * ABORT        Hangup both legs of the call.
           * CONGESTION   Behave as if line congestion was encountered.
           * BUSY         Behave as if a busy signal was encountered. Th
is will also
                          have the application jump to priority n+101 if
 the
                          'j' option is set.
           * CONTINUE     Hangup the called party and allow the calling 
party
                          to continue dialplan execution at the next pri
ority.
           * GOTO:<context>^<xexten>^<priority> - Transfer the call to t
he
                          specified priority. Optionally, an extension, 
or
                          extension and priority can be specified.
           You cannot use any additional action post answer options in c
onjunction
           with this option. Also, pbx services are not run on the peer 
(called) channel,
           so you will not be able to set timeouts via the TIMEOUT() fun
ction in this macro.
    n    - This option is a modifier for the screen/privacy mode. It spe
cifies
           that no introductions are to be saved in the priv-callerintro
s
           directory.
    N    - This option is a modifier for the screen/privacy mode. It spe
cifies
           that if callerID is present, do not screen the call.
    o    - Specify that the CallerID that was present on the *calling* c
hannel
           be set as the CallerID on the *called* channel. This was the
           behavior of Asterisk 1.0 and earlier.
    O([x]) - "Operator Services" mode (Zaptel channel to Zaptel channel
             only, if specified on non-Zaptel interface, it will be igno
red).
             When the destination answers (presumably an operator servic
es
             station), the originator no longer has control of their lin
e.
             They may hang up, but the switch will not release their lin
e
             until the destination party hangs up (the operator). Specif
ied
             without an arg, or with 1 as an arg, the originator hanging
 up
             will cause the phone to ring back immediately. With a 2 spe
cified,
             when the "operator" flashes the trunk, it will ring their p
hone
             back.
    p    - This option enables screening mode. This is basically Privacy
 mode
           without memory.
    P([x]) - Enable privacy mode. Use 'x' as the family/key in the datab
ase if
           it is provided. The current extension is used if a database
           family/key is not specified.
    r    - Indicate ringing to the calling party. Pass no audio to the c
alling
           party until the called channel has answered.
    S(x) - Hang up the call after 'x' seconds *after* the called party h
as
           answered the call.
    t    - Allow the called party to transfer the calling party by sendi
ng the
           DTMF sequence defined in features.conf.
    T    - Allow the calling party to transfer the called party by sendi
ng the
           DTMF sequence defined in features.conf.
    w    - Allow the called party to enable recording of the call by sen
ding
           the DTMF sequence defined for one-touch recording in features
.conf.
    W    - Allow the calling party to enable recording of the call by se
nding
           the DTMF sequence defined for one-touch recording in features
.conf.
    k    - Allow the called party to enable parking of the call by sendi
ng
           the DTMF sequence defined for call parking in features.conf.
    K    - Allow the calling party to enable parking of the call by send
ing
           the DTMF sequence defined for call parking in features.conf.

Differenz zum internen Hilfetext in Asterisk 1.2: 

62,63d61
<     i    - Asterisk will ignore any forwarding requests it may receive
 on this
<            dial attempt.
95,96c93
<            with this option. Also, pbx services are not run on the pee
r (called) channel,
<            so you will not be able to set timeouts via the TIMEOUT() f
unction in this macro.
---
>            with this option.
105,114d101
<     O([x]) - "Operator Services" mode (Zaptel channel to Zaptel channe
l
<              only, if specified on non-Zaptel interface, it will be ig
nored).
<              When the destination answers (presumably an operator serv
ices
<              station), the originator no longer has control of their l
ine.
<              They may hang up, but the switch will not release their l
ine
<              until the destination party hangs up (the operator). Spec
ified
<              without an arg, or with 1 as an arg, the originator hangi
ng up
<              will cause the phone to ring back immediately. With a 2 s
pecified,
<              when the "operator" flashes the trunk, it will ring their
 phone
<              back.
132,135d118
<     k    - Allow the called party to enable parking of the call by sen
ding
<            the DTMF sequence defined for call parking in features.conf
.
<     K    - Allow the calling party to enable parking of the call by se
nding
<            the DTMF sequence defined for call parking in features.conf
.