This ticket shouldnt have been backported to 6.1.x. The fix version is set to 6.2.x. so-portlet is different in 6.2.x and 6.1.x. The fix broke 6.1.x.
Also, please file SO related tickets in the SOS project.
PASSED Manual Testing using the following steps:
Tomcat 7.0.40 + MySQL 5. Portal 6.2.x. GIT ID: cf60e9ef9b44c04d52ec45714f463bf1f76dae7a.
Plugins 6.2.x EE GIT ID: 33a38f40eee16133eb026726c988fe02cd2dc887.
Portlet builds and no compile errors.