Help flex is there anybody ?

There seems to be a fundamental conflict to compile kbabel-3.4.3
with flex-2.5.4a. Flex is to old or is it libstdc++-v3 of gcc-3.4.4 ?

System:
kernel 2.6.14
glibc-2.3.2
gcc-3.4.4
gettext-0.14.5

Bug:
make[4]: Entering directory 
`(makedir)/kde-3.4.3/kdesdk-3.4.3/kbabel/common/libgettext' 
 if /bin/sh ../../../libtool --silent --tag=CXX --mode=compile g++ 
-DHAVE_CONFIG_H -I. -I. -I../../..   -DQT_THREAD_SUPPORT  -D_REENTRANT  
-Wno-long-long -Wundef -ansi -D_XOPEN_SOURCE=500 -D_BSD_SOURCE -Wcast-align 
-Wconversion -Wchar-subscripts -Wall -W -Wpointer-arith -O2 -Wformat-security 
-Wmissing-format-attribute -Wno-non-virtual-dtor -fno-exceptions 
-fno-check-new -fno-common -DQT_CLEAN_NAMESPACE -DQT_NO_ASCII_CAST 
-DQT_NO_STL -DQT_NO_COMPAT -DQT_NO_TRANSLATION  -MT pofiles.lo -MD -MP -MF 
".deps/pofiles.Tpo" -c -o pofiles.lo pofiles.cc; \ 
 then mv -f ".deps/pofiles.Tpo" ".deps/pofiles.Plo"; else rm -f 
".deps/pofiles.Tpo"; exit 1; fi 
 In file included 
from /usr/lib/gcc/i686-pc-linux-gnu/3.4.4/../../../../include/c++/3.4.4/backward/iostream.h:31, 
                  from /usr/local/include/FlexLexer.h:47, 
                  from pofiles.cc:241: 
 /usr/lib/gcc/i686-pc-linux-gnu/3.4.4/../../../../include/c++/3.4.4/backward/backward_warning.h:32:2: 
warning: #warning This file includes at least one deprecated or antiquated 
header. Please consider using one of the 32 headers found in section 17.4.1.2 
of the C++ standard. Examples include substituting the <X> header for the 
<X.h> header for C++ includes, or <iostream> instead of the deprecated header 
<iostream.h>. To disable this warning use -Wno-deprecated. 
 In file included from /usr/local/include/FlexLexer.h:47, 
                  from pofiles.cc:241: 
 /usr/lib/gcc/i686-pc-linux-gnu/3.4.4/../../../../include/c++/3.4.4/backward/iostream.h:36: 
error: `istream' is already declared in this scope 
 pofiles.cc:433:5: warning: "YY_STACK_USED" is not defined 
 pofiles.cc: In member function `virtual int GettextBaseFlexLexer::yylex()': 
 pofiles.cc:715: error: cannot convert `std::istream*' to `istream*' in 
assignment 
 ....