crash on scroll

[Edwin Leuven]

on opening the userguide and scrolling down with the mouse lyx crashes

opening the userguide and clicking on 'navigate' in the menu has the 
same effect



Assertion triggered in T& boost::optional<T>::operator*() [with T = int] 
by failing check "m_initialized" in file 
../../lyx-devel/boost/boost/optional.hpp:193

Program received signal SIGABRT, Aborted.
[Switching to Thread 1084795456 (LWP 486)]
0xffffe002 in ?? ()
(gdb) bt
#0  0xffffe002 in ?? ()
#1  0x42028c55 in abort () from /lib/tls/libc.so.6
#2  0x082ed3d3 in lyx::support::abort() ()
    at ../../../lyx-devel/src/support/abort.C:19
#3  0x0809b9b6 in boost::assertion_failed(char const*, char const*, char 
const*, long) (expr=0x833ba40 "m_initialized",
    function=0x833b740 "T& boost::optional<T>::operator*() [with T = int]",
    file=0x833b9e0 "../../lyx-devel/boost/boost/optional.hpp", line=193)
    at ../../lyx-devel/src/boost.C:56
#4  0x080d2ae4 in ParConstIterator::operator++() (this=0xbfffe554)
    at optional.hpp:193
#5  0x0811f07a in ownerPar(Buffer const&, InsetOld const*) ([EMAIL PROTECTED],
    inset=0x85f3380) at ../../lyx-devel/src/paragraph_funcs.C:589
#6  0x081bddbf in InsetNewline::draw(PainterInfo&, int, int) const (
    this=0x85f3380, [EMAIL PROTECTED], x=224, y=78)
    at ../../../lyx-devel/src/insets/insetnewline.C:90
#7  0x08124b33 in (anonymous namespace)::RowPainter::paintInset(int) (
    this=0xbfffe834, pos=137911848) at ../../lyx-devel/src/rowpainter.C:198
#8  0x0812537a in (anonymous namespace)::RowPainter::paintFromPos(int&) (
    this=0xbfffe834, [EMAIL PROTECTED]) at 
../../lyx-devel/src/rowpainter.C:350
#9  0x081271ee in (anonymous namespace)::RowPaint