NewsCoaster is free of Y2000 bugs as far as I am aware, as is the Amiga.
AmigaDOS routines are used for the handling of dates. There are two-digit fields, but if the year is smaller than 78, it is assumed to be in the 21st Century, and not the 20th Century. This means that dates will be handled correctly in 2000 and onwards, but will fail in 2078. If anyone's still using NewsCoaster then, I'll have to fix it...
See www.amiga.com for details on the (few) problems the Amiga will encounter after certain dates (beyond 2000).