wget http://ftp.sunet.se/pub/gnu/gmp/gmp-4.2.2.tar.bz2
tar -xjvf gmp-4.2.2.tar.bz2
cd gmp-4.2.2
./configure
make
make check
make install

vi /var/cpanel/easy/apache/rawopts/all_php5
add
–with-gmp
to this file and recompile php with default settings
/scripts/easyapache


Thats all, cheers