Version:           3.5.5 (using KDE 3.5.5, Debian Package 4:3.5.5a.dfsg.1-3 (4.0))
Compiler:          Target: i486-linux-gnu
OS:                Linux (i686) release 2.6.18p4s

I went to this web: http://www.entradas.com/entradas/a002001.do?identidad=1&idcanal=2&idrecinto=1114&idprov=28&idobra=55418 and notice that didn't work properly. I enable the javascript console debugger and enter the expression: enviarfecha('20061123');

Then konqueror crashed when I pressed enter with this backtrace:
Using host libthread_db library "/lib/tls/i686/cmov/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread -1500702496 (LWP 6547)]
[KCrash handler]
#6  KJS::KJSDebugWin::slotEval (this=0x90d2920)
    at /home/sid-user/kdelibs/kdelibs-3.5.5/./khtml/ecma/kjs_debugwin.cpp:618
#7  0xa5f82960 in KJS::KJSDebugWin::qt_invoke (this=0x90d2920, _id=81, 
    _o=0xafd547dc) at ./kjs_debugwin.moc:365
#8  0xa7286cb3 in QObject::activate_signal (this=0x90e0d98, clist=0x90e33b8, 
    o=0xafd547dc) at kernel/qobject.cpp:2356
#9  0xa7287744 in QObject::activate_signal (this=0x90e0d98, signal=18)
    at kernel/qobject.cpp:2325
#10 0xa763d605 in QTextEdit::returnPressed (this=0x90e0d98)
    at .moc/debug-shared-mt/moc_qtextedit.cpp:698
#11 0xa741c5da in QTextEdit::keyPressEvent (this=0x90e0d98, e=0xafd54f70)
    at widgets/qtextedit.cpp:1292
#12 0xa5f5da47 in KJS::EvalMultiLineEdit::keyPressEvent (this=0x90e0d98, 
    e=0xafd54f70)
    at /home/sid-user/kdelibs/kdelibs-3.5.5/./khtml/ecma/kjs_debugwin.cpp:346
#13 0xa72bd882 in QWidget::event (this=0x90e0d98, e=0xafd54f70)
    at kernel/qwidget.cpp:4748
#14 0xa74153c6 in QTextEdit::event (this=0x90e0d98, e=0xafd54f70)
    at widgets/qtextedit.cpp:1216
#15 0xa721ebd6 in QApplication::internalNotify (this=0xafd554fc, 
    receiver=0x90e0d98, e=0xafd54f70) at kernel/qapplication.cpp:2635
#16 0xa7220b8a in QApplication::notify (this=0xafd554fc, receiver=0x90e0d98, 
    e=0xafd54f70) at kernel/qapplication.cpp:2392
#17 0xa7914e6e in KApplication::notify (this=0xafd554fc, receiver=0x90e0d98, 
    event=0xafd54f70)
    at /home/sid-user/kdelibs/kdelibs-3.5.5/./kdecore/kapplication.cpp:550
#18 0xa71b2445 in QApplication::sendSpontaneousEvent (receiver=0x90e0d98, 
    event=0xafd54f70) at kernel/qapplication.h:523
#19 0xa71a36a9 in QETWidget::translateKeyEvent (this=0x90e0d98, 
    event=0xafd552a8, grab=false) at kernel/qapplication_x11.cpp:5636
#20 0xa71af6d3 in QApplication::x11ProcessEvent (this=0xafd554fc, 
    event=0xafd552a8) at kernel/qapplication_x11.cpp:3493
#21 0xa71c5cb2 in QEventLoop::processEvents (this=0x808c5f0, flags=4)
    at kernel/qeventloop_x11.cpp:192
#22 0xa7239129 in QEventLoop::enterLoop (this=0x808c5f0)
    at kernel/qeventloop.cpp:198
#23 0xa7238f4a in QEventLoop::exec (this=0x808c5f0)
    at kernel/qeventloop.cpp:145
#24 0xa722076f in QApplication::exec (this=0xafd554fc)
    at kernel/qapplication.cpp:2758
#25 0xa6667495 in kdemain (argc=3, argv=0x807bf08)
    at /home/sid-user/kdebase/kdebase-3.5.5/./konqueror/konq_main.cc:206
#26 0xa7f7b524 in kdeinitmain (argc=3, argv=0x807bf08) at konqueror_dummy.cc:3
#27 0x0804e457 in launch (argc=3, _name=0x80876ec "konqueror", 
    args=0x8087736 "", cwd=0x0, envc=0, envs=0x808773b "", reset_env=false, 
    tty=0x0, avoid_loops=false, startup_id_str=0x8050d2e "0")
    at /home/sid-user/kdelibs/kdelibs-3.5.5/./kinit/kinit.cpp:673
#28 0x0804ecf9 in handle_launcher_request (sock=9)
    at /home/sid-user/kdelibs/kdelibs-3.5.5/./kinit/kinit.cpp:1240
#29 0x0804f092 in handle_requests (waitForPid=0)
    at /home/sid-user/kdelibs/kdelibs-3.5.5/./kinit/kinit.cpp:1443
#30 0x080502b1 in main (argc=5, argv=0xafd55fb4, envp=0xafd55fcc)
    at /home/sid-user/kdelibs/kdelibs-3.5.5/./kinit/kinit.cpp:1909
#31 0xa7ce8ea8 in __libc_start_main () from /lib/tls/i686/cmov/libc.so.6
#32 0x0804b911 in _start () at ../sysdeps/i386/elf/start.S:119

I'm sorry to say that I have been unable to reproduce this.