I am a J2 visa holder who was given work permit for 4 years from 9/2005 to 9/2009. If my spouse's J1 visa will not expire until 2011, am I eligible to apply for work permit extension? Is it true that 4 year is the longest time for a J2's work permit?
Thank you in advance for your help.

You can file for extension as long as the principle J-1 holder still maintains his status.