Solution The supplementary document of the ThinkPad system's "Service and Troubleshooting Guide" has the following information in "Wireless regulatory information - USA Federal Communications Commission (FCC)" section:
Use of wireless options
Please make sure of the following conditions on use of wireless features.
Visit the site at www.pc.ibm.com/qtechinfo/MIGR-43693.html and confirm the updated list of RF option devices that have been approved to cooperate with the integrated wireless feature.
When you use any other RF option device that is not listed on the site, all other wireless features including the integrated transmitter in your ThinkPad computer are required to be turned off.
Users are requested to follow the RF Safety instructions on wireless option devices that are included in the RF option device's user's manual.