I'm actually fixing someone elses code, based on the actual code the fix might be as simple as:

if (lc($b) eq lc($a))
{
  print "do something...\n";
}
[download]

However the first answer (using /\Q$a\E/) has immediately fixed the issue and knowing the data it will be a permanent fix for the issue... it also taught me something that I probably have come across in the past... 20+years working with perl and I still learn something new every so often... :)

Thanks, all.