What files are you referring to?
Traditionally, UNIX files do not have a creation date. UFS on Solaris doesn't record or track any creation timestamp.
The timestamps on UNIX are access time, modification time, and inode change time.
You can grab and compile the 'stat' program to see them easily, or I might use 'perl' to view them.
# stat field 8 is atime, 9 is mtime, and 10 is ctime
%perl -le 'print scalar localtime ((lstat $ARGV[0])[9])' <name_of_the_file>
If you truly just want the date in that format, I'd go with:
% perl -MPOSIX -le 'print strftime "%Y-%m-%d",localtime ((stat $ARGV[0])[9])' <name_of_the_file>
--
Darren