[Windows Mobile Development and Hacking General] HappyGoat:
Possibly more AT Commands (from an old post from W4XY):

Found some interesting things:

TAPI --> TSPI* --> RIL --> RILGSM

* maybe RIL.dll is the tspi (not checked yet)

the following devices are involved:

RIL1:
COM2:
COM9:
WAV1:

It seems that COM2 is a basic AT command capable port (hardwired to the phone). COM9 seems to be a "virtual" port for data transmissions. RIL1 is only a device identifier (maybe tspi connects to it).

RIL = Radio Interface Layer
TSPI = TAPI Service Provider

If anybody got some time here are all of the extracted strings which looked like AT commands (have fun):

+CLCC: AT
+CSQ: 20,99
0
AT+COPS=0

AT+COPS=1,2,"%s"
AT+CPIN="%s"
AT+CFUN=1
ATH
AT+CFUN=0
ATD*99#
AT+CGQMIN=1
AT+CGQREQ=1
at%%talk=%d,%x
ATA
AT+CBST=7,0,1
AT+CBST=71,0,1
AT+CBST=%u,%u,%u
+FCLASS+1;D
+VTS=%c;
AT+CLCC
AT+CUSD=1,"2A333723",15
AT+CHLD=4
AT+CHLD=3
AT+CHLD=2%u
AT+CHLD=2
AT+CHLD=1%u
AT+CHLD=1
AT+CHLD=0
,"%s",%u
AT+CTFR="%s",%u
AT+CPAS
+CPAS:
AT%%ALS=%u
AT%ALS?
%ALS:
SM
BR
BM
AD
ON
LD
EN
AC
AG
AB
NS
IR
AI
OX
OI
AO
PC
PP
PU
PN
FD
P2
SC
PF
PS
CS
AT+ES=?
AT+DS=?
AT+CGSMS=?
AT+CGQMIN=?
AT+CGQREQ=?
AT+CGDCONT=?
AT+CGCLASS=?
AT+CHSD;+CHSN=?
AT+CCFC=?
AT+CPWD=?
AT+CLCK=?
AT+CPOL=?
AT+CMGL=?
AT+CPMS=?
AT+CSMS=?
AT+CPBF=?
AT+CPBR=?
AT+CPBS=?
AT+CFUN=?
AT+CRLP=?
AT+CBST=?
AT+CHLD=?
AT+VTD=?
+VTD: +CHLD:
+CBST:
+CRLP:
+CFUN:
+CPBS:
+CPBR:
+CPBF:
+CSMS:
+CPMS:
+CMGL:
+CPOL:
+CLCK:
+CPWD:
+CCFC:
+CHSN:
+CHSD:
ATO
AT+CRSM=192,28438,0,0,15
AT+CHST?;+CHSN?;+CHSU?
+CHSU:
+CHST:
;+CHSU=%u
;+CHSN=
AT+CHST=
AT+CHSC
+CHSC:
AT+CBST?
AT+CBST=
AT+CRLP?
AT+CRLP=
AT+DS?

+DS:
AT+DS=
AT+ES?
+ES:
AT+ES=
AT%CGMI;%CGMN;%CGMR;%CGSN
AT+CFUN?
AT+CFUN=%u
AT+CPBS?
AT+CPBS="%s"
AT+CPBR=%u,%u
AT+CPBW=%u,"%s",%u
AT+CPBW=,"%s",%u
AT+CPBW=%u
AT+CRSM=%u
+CRSM:
AT%SATR=
AT+CAOC=0;+CACM?;+CAMM?;+CPUC?
+CPUC:
+CAMM: "
+CACM: "
+CAOC: "
+CPUC="%s","%u.%.4u"
+CAMM=%u
+CACM=
+CSQ: AT+CSQ
AT%LCKGID=?
AT%%LCKGID=0,%s
AT%%LCKGID=1,%s
AT%LCKGID?
AT%%GID?%u
AT%%CHKGID?%s
AT%%GID=%s
AT%CLNGID
AT%CNTGID
AT%%CGPPP=%u
AT%%CPRIM="CST","CONFIG L1_PARAMS=<0,%X>"
AT%%L1T=1
AT%EMREAD
AT%EMEXIT
AT%EMINIT
AT%BAND
AT%%CHG900
AT%%CHG1900
AT%%CHGDUAL
AT%%talk?%u
AT%%SIDLCK=0,%s
AT%%SIDLCK=1,%s
AT%SIDLCK?
AT%%SID?%u
AT%SIDCHK
AT%%SID=%u
AT%SIDCLN
AT%SIDCNT
AT$V0
AT+CSMS?;+CPMS?
+CPMS=
+CSMS=%u
AT+CSCA?
+CSCA:
;+CSAS
+CSCA="%s",%u
AT+CSCB?
+CSCB:
AT+CNMI=2,2,2,1,0
%s,"%s" AT+CSCB=%d
AT+CMGR=%u

+CMGR:
AT+CMGD=%u
AT+CMGW=%u,%u
%s
+CMGW:
AT+%s=%u
%s
AT+CMMS=1;+%s=%u
%s
CMGS
CMGC
+CMGC:
+CMGS:
AT+CMSS=%u
AT+CMMS=1;+CMSS=%u
+CMSS:
AT+CNMA=%u
AT+CNUM
+CNUM:
AT+COPS=?
+COPS:
AT+CPOL=,%u;+CPOL?
0,"%s"
1,"%s"
2,"%s"
AT+CPOL=%u,
AT+CPOL=,
AT+CPOL=%u
AT+COPS=3,%u;+COPS?
AT+COPS=%u
AT+COPS=2
AT+CREG?
+CREG:
PH-CORP PUK
PH-CORP PIN
PH-SP PUK
PH-SP PIN
PH-NETSUB PUK
PH-NETSUB PIN
PH-NET PUK
PH-NET PIN
SIM PUK2
SIM PIN2
PH-FSIM PUK
PH-FSIM PIN
PH-SIM PIN
SIM PUK
SIM PIN
READY

> 4

ERROR

OK
ADC
+EMU:
+CMS ERROR:
+CME ERROR:
+EXT ERROR:
%SATA:
%SATN:
%SATI:
+SOUND:
+CHSR:
+CUSD:
+CDSI:
+CBMI:
+CMTI:
+CDS:
+CBM:
+CMT:
+CCCM:
+CSSI:
+CSSU: 5
+CCWA:
+COLP:
+CLIP:
+CR:
+CRING:
+CGREG:
%CPI:
RESET_ME
AT-Command Interpreter ready
CONNECT 9600

> -HTC:
-HTC:
+HTC:
>
VOICE
FAX
REL SYNC
REL ASYNC
SYNC
ASYNC
AUX
REL SYNC
REL ASYNC
SYNC
ASYNC
Z;S0=0;E0;Q0;V0;X3;&C1|+CMEE=1;+CRC=1;+CR=1;+CMOD=0; +CREG=1|+FCLASS=0;+CSSN=0,1;+CLIP=1;+COLP=1;+CCWA=1; +CMGF=0;+CSCS="HEX"|+CGREG=1|+CUSD=1|%LANG=2|%CARRIER=2|
AT+CPIN?
%%CGPPP=%u|
%%CPRIM="GMM","CONFIG MULTISLOT_CLASS=<%u>"|
+CLIR=%u|
$AD=%u;$AU=%u|
AT+CSCB=0,"%s"
AT+CSCB=1,"0-65535";+CSAS
AT+CNMI=2,2,0,1,0
AT+CIMI
+CPIN:
AT+CPIN="%s"
AT+CLCK="%s",2
AT+CLCK="%s",2,"%s"
AT+CLCK="%s",%u
AT+CLCK="%s",%u,"%s"
ATD**05%s*%s*%s*%s#
AT+CPWD="%s","%s","%s"
ATD*%u
ATD*#%u
AT+CLCK="%s",2
AT+CLCK="%s",%u
ATD*03*330*%s*%s*%s#
AT+CLIP?
AT+CLIP=%d
AT+CLIR?
AT+CLIR=0
+CLIR:
AT+CLIR=%u
AT+COLP?
AT+COLP=%d
AT+CCUG?
+CCUG:
AT+CCUG=%u
%s**%u#
D#%s
D*%s
D*#%s
D##%s
%s
,,,%u
+CCFC=%u,3,"%s",%u,%u
+CCFC=%u,%u,,,%u
AT+CCWA=1,2,%u
AT+CCWA=1,2
ATD%c43*%u#
ATD%c43#
A T D % s
AT+CUSD=2
$AU=%u
$AD=%u
AT+CMUT?
+CMUT:
AT+CMUT=%u
PAD NULL X25 PPP OSPIH IP
+CGDCONT:
AT+CGDCONT?
AT+CGDCONT=%u,
AT+CGDCONT=%u
+CGQREQ:
+CGQMIN:
AT+CGQREQ?
AT+CGQMIN?
AT%s=%u,
+CGQREQ
+CGQMIN
AT%s=%u
AT+CGATT=%u
+CGATT:
AT+CGATT?
AT+CGACT=%u,%u
+CGACT:
AT+CGACT?
+CGPADDR:
AT+CGPADDR=%u
AT+CGANS=%u,
AT+CGREG?
+CGCLASS:
AT+CGCLASS?
AT+CGCLASS="%s"
+CGSMS:
AT+CGSMS?
AT+CGSMS=%u
AT#%02X%s%02X
%SIDCNT:
%SID:
%SIDLCK:
%TALK:
+BAND:
+EMS:
+EMD:
%CNTGID:
%LCKGID:
%GID: