update message attribute

Synopsis:

(update message attribute attribute 
		to value)

Description:

Updates the message attribute attribute to the value value.

Example:

(update message attribute "money" to 150)

Contact: Fulvio Frapolli (fulvio . frapolli //at// unifr . ch), Amos Brocco (amos . brocco //at// unifr . ch)
* Remove spaces and replace //at// with @