Version:           4.5.3 (using KDE 3.5.3 Level "a" , unofficial build of SUSE )
Compiler:          Target: x86_64-suse-linux
OS:                Linux (x86_64) release 2.6.16.13-4-default

Reproduce:
1) Launch KWrite.
2) Save new file as "bug.c".
3) Select C style indenting.
4) Write this:
if (a == b)
{
} else
5) After last line entered, application crashes. KCrash window informs about signal 11 (SIGSEGV).

Backtrace:
Using host libthread_db library "/lib64/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread 47541875322448 (LWP 7229)]
[KCrash handler]
#5  0x00002b3d35682333 in KateTextLine::stringAtPos (
    this=<value optimized out>, pos=4294967295, match=<value optimized out>)
    at ./kate/part/katetextline.cpp:191
#6  0x00002b3d35700137 in KateCSmartIndent::calcContinue (this=0x94aa70, 
    start=@0x7fff7a764980, end=@0x7fff7a764b20)
    at ./kate/part/kateautoindent.cpp:894
#7  0x00002b3d35701025 in KateCSmartIndent::calcIndent (this=0x94aa70, 
    begin=@0x7fff7a764b20, needContinue=true)
    at ./kate/part/kateautoindent.cpp:778
#8  0x00002b3d357013e8 in KateCSmartIndent::processNewline (this=0x94aa70, 
    begin=@0x7fff7a764b20, needContinue=true)
    at ./kate/part/kateautoindent.cpp:595
#9  0x00002b3d357133e1 in KateDocument::newLine (this=0x666180, 
    c=@0x7fff7a764b90, v=<value optimized out>)
    at ./kate/part/katedocument.cpp:3001
#10 0x00002b3d357230f0 in KateViewInternal::doReturn (this=0x784cb0)
    at ./kate/part/kateviewinternal.cpp:898
#11 0x00002b3d35733687 in KateViewInternal::keyPressEvent (this=0x784cb0, 
    e=0x7fff7a7654a0) at ./kate/part/kateviewinternal.cpp:2477
#12 0x00002b3d3571f656 in KateViewInternal::eventFilter (this=0x784cb0, 
    obj=0x784cb0, e=0x7fff7a7654a0) at ./kate/part/kateviewinternal.cpp:2409
#13 0x00002b3d31d67492 in QObject::activate_filters (this=0x784cb0, 
    e=0x7fff7a7654a0) at kernel/qobject.cpp:903
#14 0x00002b3d31d674e7 in QObject::event (this=0x784cb0, e=0x7fff7a7654a0)
    at kernel/qobject.cpp:735
#15 0x00002b3d31d9a5c8 in QWidget::event (this=0x6dcfb0, e=0xffffffff)
    at kernel/qwidget.cpp:4678
#16 0x00002b3d31d10a95 in QApplication::internalNotify (
    this=<value optimized out>, receiver=0x784cb0, e=0x7fff7a7654a0)
    at kernel/qapplication.cpp:2636
#17 0x00002b3d31d11d69 in QApplication::notify (this=0x7fff7a765990, 
    receiver=0x784cb0, e=0x7fff7a7654a0) at kernel/qapplication.cpp:2393
#18 0x00002b3d316feb38 in KApplication::notify (this=0x7fff7a765990, 
    receiver=0x784cb0, event=0x7fff7a7654a0) at ./kdecore/kapplication.cpp:552
#19 0x00002b3d31cb71ae in QETWidget::translateKeyEvent (this=0x784cb0, 
    event=<value optimized out>, grab=<value optimized out>)
    at kernel/qapplication.h:523
#20 0x00002b3d31cb81b0 in QApplication::x11ProcessEvent (this=0x7fff7a765990, 
    event=0x7fff7a765760) at kernel/qapplication_x11.cpp:3493
#21 0x00002b3d31cc725f in QEventLoop::processEvents (this=0x57d020, flags=4)
    at kernel/qeventloop_x11.cpp:192
#22 0x00002b3d31d257a1 in QEventLoop::enterLoop (this=0x6dcfb0)
    at kernel/qeventloop.cpp:198
#23 0x00002b3d31d2564a in QEventLoop::exec (this=0x6dcfb0)
    at kernel/qeventloop.cpp:145
#24 0x00002b3d30471236 in kdemain () from /opt/kde3/lib64/libkdeinit_kwrite.so
#25 0x00002b3d305bc154 in __libc_start_main () from /lib64/libc.so.6
#26 0x0000000000400569 in _start ()