Hello,
I have downloaded and set up sipXtapi (http://www.sipfoundry.org/temp/sipXtapi/sipXtapi_SRC_2006-03-10.tgz) on my KDE environment
Then I tested your ReceiveCall project :

[osadmin@hmwd8424 ReceiveCall]$ ./ReceiveCall -a password -u user -i sip:user@mydomain -m realm

This appears:
EVENT_CATEGORY_LINESTATE::PROVISIONED::PROVISIONED_NORMAL
EVENT_CATEGORY_LINESTATE::REGISTERING::REGISTERING_NORMAL
<-> Type LOCAL, Interface: eth0, Ip 10.186.19.195, Port 5060
<-> Type LOCAL, Interface: vmnet1, Ip 192.168.253.1, Port 5060
<-> Type LOCAL, Interface: vmnet8, Ip 192.168.133.1, Port 5060
<-> Type LOCAL, Interface: eth0, Ip 10.186.19.195, Port 5060
<-> Type LOCAL, Interface: vmnet1, Ip 192.168.253.1, Port 5060
<-> Type LOCAL, Interface: vmnet8, Ip 192.168.133.1, Port 5060
EVENT_CATEGORY_LINESTATE::REGISTERED::REGISTERED_NORMAL

And when I place a call with another softphone (X-lite) ; a segmentation fault appears on my Shell:
..
<-> Type LOCAL, Interface: vmnet1, Ip 192.168.253.1, Port 5060
<-> Type LOCAL, Interface: vmnet8, Ip 192.168.133.1, Port 5060
EVENT_CATEGORY_LINESTATE::REGISTERED::REGISTERED_NORMAL
Segmentation fault
[osadmin@hmwd8424 ReceiveCall]$

Below the last generated logs :
2006-07-24T14:29:14.500355Z":102:CP:DEBUG:hmwd8424.toulouse.francetelecom.fr:CallManager-21:B597ABB0:sipXtapi:"Message callid: 464dbd79e73bad6fNmYwOGYwZjk0OGE2NWFjMjQ1YWUxMjVkOWU5YzIxMjM.\n"

"2006-07-24T14:29:14.510713Z":103:CP:DEBUG:hmwd8424.toulouse.francetelecom.fr:CallManager-21:B597ABB0:sipXtapi:"Creating new call for incoming SIP message\n"

"2006-07-24T14:29:14.523834Z":104:CP:DEBUG:hmwd8424.toulouse.francetelecom.fr:Call-29:B5879BB0:sipXtapi:"CpCall::handleMessage message type: 5 subtype 1\n"
~

I used gdb command :

[New Thread -1249403984 (LWP 25349)]

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread -1249403984 (LWP 25349)]
0x008c8f83 in strlen () from /lib/tls/libc.so.6
(gdb) bt
#0 0x008c8f83 in strlen () from /lib/tls/libc.so.6
#1 0x0089d1a5 in vfprintf () from /lib/tls/libc.so.6
#2 0x008b51eb in vsprintf () from /lib/tls/libc.so.6
#3 0x008a251b in sprintf () from /lib/tls/libc.so.6
#4 0x005332ae in CpCallManager::getNewCallId (this=0x8ad5a60, callIdPrefix=0x5ca25c "s", callId=0x8b05220) at cp/CpCallManager.cpp:511
#5 0x00533389 in CpCallManager::getNewSessionId (this=0x8ad5a60, callId=0x8b05220) at cp/CpCallManager.cpp:409
#6 0x00528bd6 in Connection::Connection$base () at tapi/SipXMessageObserver.cpp:39
#7 0x0054260c in SipConnection (this=0x8b05220, outboundLineAddress=0x5cb5e6 "", isEarlyMediaFor180Enabled=1, callMgr=0x8ad5a60, call=0x8b01518,
    mediaInterface=0x8afcdd8, sipUA=0x8a999b8, offeringDelayMilliSeconds=5000, sessionReinviteTimer=64, availableBehavior=100,
    forwardUnconditionalUrl=0x8b03980 "", busyBehavior=200, forwardOnBusyUrl=0x8b039f8 "") at cp/SipConnection.cpp:81
#8 0x0054066f in CpPeerCall::handleSipMessage (this=0x8b01518, pEventMessage=0x8b05200) at cp/CpPeerCall.cpp:619
#9 0x005411c9 in CpPeerCall::handleCallMessage (this=0x8b01518, eventMessage=@0x8b05200) at cp/CpPeerCall.cpp:2089
#10 0x0052d423 in CpCall::handleMessage (this=0x8b01518, eventMessage=@0x8b05200) at cp/CpCall.cpp:592
#11 0x002646f9 in OsServerTask::run (this=0x8b01518, pArg=0x0) at os/OsServerTask.cpp:152
#12 0x0027a203 in OsTaskLinux::taskEntry (arg=0x8b01518) at os/linux/OsTaskLinux.cpp:654
#13 0x00ad2371 in start_thread () from /lib/tls/libpthread.so.0
#14 0x009279be in clone () from /lib/tls/libc.so.6


Could help me to resolve this problem ?

Thank you in advance

Luc