The latest round of linux updates brought up one specific issue with perl, the error in question was:

dualvar is only available with the XS version of Scalar::Util at /usr/lib/perl5/site_perl/5.8.8/Mail/Reporter.pm line 14
BEGIN failed–compilation aborted at /usr/lib/perl5/site_perl/5.8.8/Mail/Reporter.pm line 14.
Compilation failed in require at (eval 10) line 3.
…propagated at /usr/lib/perl5/5.8.8/base.pm line 85.
BEGIN failed–compilation aborted at /usr/lib/perl5/site_perl/5.8.8/Mail/Transport.pm line 12.

It has been highlighted here:

https://bugzilla.redhat.com/show_bug.cgi?id=434574

So essentially the module Scalar::Util::dualvar appears to have been depreciated, however several modules do complain when this is not there.
To correct run the following from command line:

perl -MCPAN -e shell
force install Scalar::Util

This highlight how important it is to review updates prior to accepting their install as you never know what might break. Ideally having a staging server prior to roll out would be ideal but not everyone has so becoming familiar with your server/site to know what might happen and running updates at times that causes the less impact is advised.