Compilação de PHP em Mandriva 2006.0 Free

Olá amigos..
Preciso compilar o php com suporte a Firebird, porém está ocorrendo o seguinte erro:

root@server php512]# ./configure --with-apxs2filter=/usr/sbin/apxs --with-interbase=/opt/firebird --program-prefix= --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc --datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib --libexecdir=/usr/libexec --localstatedir=/var --with-ttf --with-xml --with-zlib --with-mysql=shared,/usr

loading cache ./config.cache
checking for Cygwin environment... no
checking for mingw32 environment... no
checking for egrep... grep -E
checking for a sed that does not truncate output... /bin/sed
checking host system type... i686-pc-linux-gnu
checking target system type... i686-pc-linux-gnu
checking for gcc... gcc
checking whether the C compiler (gcc ) works... yes
checking whether the C compiler (gcc ) is a cross-compiler... no
checking whether we are using GNU C... yes
checking whether gcc accepts -g... yes
checking whether gcc and cc understand -c and -o together... yes
checking how to run the C preprocessor... gcc -E
checking for AIX... no
checking whether ln -s works... yes
checking if compiler supports -R... no
checking if compiler supports -Wl,-rpath,... yes
checking for re2c... no
configure: warning: You will need re2c 0.9.11 or later if you want to regenerate PHP parsers.
checking for gawk... gawk
checking for bison... no
checking for byacc... no
checking for bison version... invalid
configure: warning: bison versions supported for regeneration of the Zend/PHP parsers: 1.28 1.35 1.75 1.875 2.0 2.1 (found: none).
checking for flex... lex
checking for yywrap in -ll... no
checking lex output file root... ./configure: line 3246: lex: command not found
configure: error: cannot find output from lex; giving up
[root@server php512]#

o que pode estar causando isso?

Antecipadamente meus agradecimentos pela(s) ajuda(s).