Do you have a backtrace and/or valgrind log?

#4  0xb5425fa4 in JabberCapabilitiesManager::capabilitiesEnabled (this=0x0,
    jid=@0x8504d84)
    at /data/dmueller/src/kde/3.5/kdenetwork/kopete/protocols/jabber/jabbercapabilitiesmanager.cpp:56
6
No locals.
#5  0xb54026b6 in JabberResource::setResource (this=0x8504d48,
    resource=@0xbfa2d380)
    at /data/dmueller/src/kde/3.5/kdenetwork/kopete/protocols/jabber/jabberresource.cpp:90
No locals.
#6  0xb5404f1a in JabberResourcePool::addResource (this=0x84d8718,
    jid=@0xbfa2d400, resource=@0xbfa2d380)
    at /data/dmueller/src/kde/3.5/kdenetwork/kopete/protocols/jabber/jabberresourcepool.cpp:114
        mResource = (class JabberResource *) 0x8504d48
        __PRETTY_FUNCTION__ = "void JabberResourcePool::addResource(const XMPP::Jid&, const XMPP::Res
ource&)"
#7  0xb53fccdc in JabberAccount::setPresence (this=0x8346c68,
    status=@0xbfa2d4b8)
    at /data/dmueller/src/kde/3.5/kdenetwork/kopete/protocols/jabber/jabberaccount.cpp:1041
        newStatus = {v_priority = 5, v_show = {d = 0x8357638}, v_status = {
    d = 0x83576a8}, v_key = {d = 0x810f610}, v_timeStamp = {d = {
      jd = 2454021}, t = {ds = 70676694}}, v_isAvailable = false,
  v_isInvisible = false, v_xsigned = {d = 0x810f610}, v_songTitle = {
    d = 0x810f610}, v_capsNode = {d = 0x8504ae0}, v_capsVersion = {
    d = 0x8504b00}, v_capsExt = {d = 0x8510660}, ecode = -1, estr = {
    d = 0x810f610}, d = 0x8375618}
        jid = {f = {d = 0x8346d00}, b = {d = 0x8346d00}, d = {d = 0x83935c0},
  n = {d = 0x83671e0}, r = {d = 0x810f610}, valid = true}
        newResource = {v_name = {d = 0x8349b30}, v_status = {v_priority = 5,
    v_show = {d = 0x8357638}, v_status = {d = 0x83576a8}, v_key = {
      d = 0x810f610}, v_timeStamp = {d = {jd = 2454021}, t = {ds = 70676694}},
    v_isAvailable = false, v_isInvisible = false, v_xsigned = {d = 0x810f610},
    v_songTitle = {d = 0x810f610}, v_capsNode = {d = 0x8504ae0},
    v_capsVersion = {d = 0x8504b00}, v_capsExt = {d = 0x8510660}, ecode = -1,
    estr = {d = 0x810f610}, d = 0x8375618}, d = 0x11c}
        __PRETTY_FUNCTION__ = "void JabberAccount::setPresence(const XMPP::Status&)"
#8  0xb53fd23b in JabberAccount::disconnect (this=0x8346c68,
    reason=Kopete::Account::Manual)
    at /data/dmueller/src/kde/3.5/kdenetwork/kopete/protocols/jabber/jabberaccount.cpp:653
        __PRETTY_FUNCTION__ = "void JabberAccount::disconnect(Kopete::Account::DisconnectReason)"
#9  0xb53ff9e8 in ~JabberAccount (this=0x8346c68)
    at /data/dmueller/src/kde/3.5/kdenetwork/kopete/protocols/jabber/jabberaccount.cpp:120
No locals.
#10 0xb7e67016 in ~Protocol (this=0x83a2138)
    at /data/dmueller/src/kde/3.5/kdenetwork/kopete/libkopete/kopeteprotocol.cpp:73
No locals.
#11 0xb53f395c in ~JabberProtocol (this=0x83a2138)
    at /data/dmueller/src/kde/3.5/kdenetwork/kopete/protocols/jabber/jabberprotocol.cpp:154
No locals.
#12 0xb7e72bf3 in ~PluginManager (this=0x8201840)
    at /data/dmueller/src/kde/3.5/kdenetwork/kopete/libkopete/kopetepluginmanager.cpp:116
No locals.
#13 0xb7e73e9f in KStaticDeleter<Kopete::PluginManager>::destructObject (
    this=0xb7f1cc78) at /opt/kde-35/include/kstaticdeleter.h:126
No locals.
#14 0xb7e74285 in ~KStaticDeleter (this=0xb7f1cc78)
    at /opt/kde-35/include/kstaticdeleter.h:131
No locals.
#15 0xb7e70580 in __tcf_0 ()
    at /data/dmueller/src/kde/3.5/kdenetwork/kopete/libkopete/kopetepluginmanager.cpp:81
No locals.
#16 0xb6085f41 in __cxa_finalize () from /lib/libc.so.6
No symbol table info available.
#17 0xb7e59aa3 in __do_global_dtors_aux () from /opt/kde-35/lib/libkopete.so.1
No symbol table info available.
#18 0xb7efcd0c in _fini () from /opt/kde-35/lib/libkopete.so.1
No symbol table info available.
#19 0xb7f653b3 in _dl_fini () from /lib/ld-linux.so.2
No symbol table info available.
#20 0xb6085c3d in exit () from /lib/libc.so.6
No symbol table info available.
#21 0xb63ed0d9 in _IceDefaultIOErrorHandler () from /usr/lib/libICE.so.6
No symbol table info available.
#22 0xb6defbc7 in KApplication::iceIOErrorHandler (this=0x0, conn=0x8181888)
    at /data/dmueller/src/kde/3.5/kdelibs/kdecore/kapplication.cpp:756
No locals.
#23 0xb6defc0f in kde_ice_ioerrorhandler (conn=0x8181888)
    at /data/dmueller/src/kde/3.5/kdelibs/kdecore/kapplication.cpp:193
No locals.
#24 0xb63f4ee1 in _IceRead () from /usr/lib/libICE.so.6
No symbol table info available.
#25 0xb63f992f in IceProcessMessages () from /usr/lib/libICE.so.6
No symbol table info available.

is this bug still valid on latest Kopete of kde 3.5.7 ?

no, thanks for the reminder. I think it wasn't kopete's fault but a miscompilation.