[imp] pecl install modules

[peter lawrie]

Just starting to install horde (H5) for the fourth time!.
Looking at the pecl install instructions
You suggest fileinfo memcache imagicj and lzf
For each I need to have a file in /etc/php.d such as fileinfo.ini
containing extension=fileinfo.so
That's fine for fileinfo because I have
# find / -name "*fileinfo.so*" -print
/usr/lib64/php/modules/fileinfo.so


However for lzf, memcache and imagick I don't have a .so file
Running pecl install imagick for instance gives
# pecl install imagick
downloading imagick-3.0.1.tgz ...
Starting to download imagick-3.0.1.tgz (93,920 bytes)
.....................done: 93,920 bytes
13 source files, building
running: phpize
sh: phpize: command not found
ERROR: `phpize' failed

I don't have phpize, it appears it is in php-devel-5.3.3-22.el6.x86_64
which I don't have (I have php-5.3.3-22 and php-common and php-cli)
but I cannot find this anywhere in yum or elsewhere. Redhat refer to it but
it does not appear to be obtainable!
Any suggestions?
Regards
Peter Lawrie