Participants are permitted to contribute up to $16,500 for the year 2011; this limit rises to $17,000 in 2012.
Additionally there is an Age 50 catch-up.
Age 50 Catch-up Provision
Participants age 50 or older at any time during calendar year are eligible to contribute an additional $5,500
to their 457(b), raising their combined contribution amount to $22,000 for 2011, and $22,500 beginning in 2012.