undefined method `save' for []:Array

hi all
when i m trying to save my tags.this error s cmng........cn anybody
help me to how to save the array

error depicting = undefined method `save' for []:Array

Hi Joe,

This list is for the discussion of patches and changes to the rails code
itself, rather than support for running it. Please ask on the talk
list, or ask in #rubyonrails in irc.freenode.com.

Good luck,
Jan