R help - Mar 2009 - Possible bug in charting: shaded region? (quantmod)

Dear Jeff and all,
I think there is bug in plotting shaded regions: the region is one bar off on
the left side. Can somebody please confirm this?

By the way, I like this quantmod package a lot! Thanks for the great work!

Regards, 
--Chang Lin
Sent from my Verizon Wireless BlackBerry