problem setting root in slc5 machine

Hi,

I am trying to run root on a SLC5 machine, but I get the following error: Error: /afs/cern.ch/sw/lcg/app/releases/ROOT/5.25.04/x86_64-slc5-gcc34-opt/root/bin/rootcint: error loading headers... Error in <ACLiC>: Dictionary generation failed! Info in <ACLiC>: Invoking compiler to check macro's validity sh: g++34: command not found
Error: Function macro1() is not defined in current scope :0:

My linux configuration is:
uname -a
Linux anl01 2.6.18-194.11.3.el5 #1 SMP Tue Aug 31 10:13:43 CEST 2010 x86_64 x86_64 x86_64 GNU/Linux

and gcc:
g++ -v
Using built-in specs.
Target: x86_64-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-libgcj-multifile --enable-languages=c,c++,objc,obj-c++,java,fortran,ada --enable-java-awt=gtk --disable-dssi --enable-plugin --with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre --with-cpu=generic --host=x86_64-redhat-linux Thread model: posix
gcc version 4.1.2 20080704 (Red Hat 4.1.2-48)

Does somebody know what could be wrong?
Thanks,

   Belen