Minus in single quoted string breaks Perl syntax highlighter

A minus character in a single quotes string breaks the Perl syntax highlighter. It does not seem to recognize the end quote and keeps highlighting text as if it was in the quotes. Also text just after the minus sign is in an unusuall colour. See attached screenshot.

Does not seem to make much difference what the text about the minus is.
'-', 'a-b', '-0' all show issues.

Double quoted strings are not affected.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: kwrite 4:4.8.4-0ubuntu0.1
ProcVersionSignature: Ubuntu 3.2.0-31.50-generic 3.2.28
Uname: Linux 3.2.0-31-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.0.1-0ubuntu12
Architecture: amd64
Date: Thu Oct 4 12:06:45 2012
ExecutablePath: /usr/bin/kwrite
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
ProcEnviron:
 TERM=xterm
 SHELL=/bin/bash
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 LANGUAGE=en_GB:en
SourcePackage: kate
UpgradeStatus: No upgrade log present (probably fresh install)