Not Alaska's call:

Advisory: TSA Security Directive

The Transportation Security Administration is implementing new security measures including a prohibition of the transportation on board domestic or international flights to or from the U.S. of printer or toner cartridges weighing 16 ounces or more. Accordingly, effective Monday, November 8, 2010, passengers are prohibited from transporting these items in either carry-on or checked baggage.

(from DL.com)

TSA.gov does not have a ready blurb but toner and ink cartridges are on the prohibited items list.