sympa cannot be build for EPEL6 ix86.
It BuildRequires: perl(Locale::Messages) which is provided by perl-libintl-perl from base RHEL/CentOS 6. This package is not provided for ix86 and is only available in the x86_64 flavor.
Sympas itself is fine with ix86, it builds fine for Fedora ix86.
I've added the following line as a workaround: