Thanks everyone for your suggestions. The correct answer was given by grw. Initially I just plugged the modules into the system without following the proper procedure. After I installed the modules using USM, the system brought the links up.
For those who read this topic and have the same problem. Beware that pulling out the modules when the system is up and running leads to IMMEDIATE REBOOT of BOTH the storage processors. Pulling out the modules when the system is powered down and disconnected from power sources leads to an additional reboot during the first boot up process after the power has been restored.