@artfulrobot
if i'm not mistaken you can do something like this:
# run every 2 minutes from 1 to 22:59
*/2 1-22 * * * foo
# run every 2 minutes between 23:00 and 23:50
0-50/2 23 * * * foo
# run every 2 minutes between 0:10 and 0:59
10-59/2 0 * * * foo
not exactly the prettiest but it should do the trick (i hope).