Using utimes, futimes, futimens, etc., it is possible to set the access and modification timestamps on a file.
Modification ti
For ext2/3 and possibly for ext4 you can do this with debugfs tool, assuming you want to change the ctime of file /tmp/foo which resides in disk /dev/sda1 we want to set ctime to 201001010101 which means 01 January 2010, time 01:01:
Warning: Disk must be unmounted before this operation
# Update ctime
debugfs -w -R 'set_inode_field /tmp/foo ctime 201001010101' /dev/sda1
# Drop vm cache so ctime update is reflected
echo 2 > /proc/sys/vm/drop_caches
Information taken from Command Line Kung Fu blog.