Two leading proxy advisory firms are telling Wal-Mart shareholders to vote against certain board members up for re-election, saying the directors neglected their responsibility in an alleged bribery scheme in its Mexican operations.

The corporate governance firms ISS and Glass Lewis Inc. recommended late last week that their shareholder clients vote not to re-elect CEO Mike Duke and former CEO Lee Scott to the board, among others.

Votes are to be tallied at the company's annual meeting next week.

The advice comes four weeks after The New York Times reported that Wal-Mart failed to notify law enforcement after its own investigators found evidence that $24 million in bribes were funneled through its Mexican unit.