Is there a way to have conditional data validation based on the contents of another cell in google spreadsheets?

Is there a way to have conditional data validation based on the contents
of another cell in google spreadsheets?

Examle Sheet:
https://docs.google.com/spreadsheet/ccc?key=0ApUbvdjb2dQUdDRIbWVxX25JR29BZHItYXdHZkR2T3c&usp=sharing
I'm wondering if there is a way to to have cell J2 be conditional on the
contents of M2, so that only a certain range of numbers (time) can be
entered into J2 based on M2? The ranges would be like so: if M2 says
"low," then J2 has to be between 1 hour and 200 hours. If it's not a
warning comes up or it doesn't allow input (either/or)...
Low = 1:00:00—200:00:00 (1—200 hours)
Medium = 200:00:01—300:00:00 (200—300 hours)
High = 300:00:01—500:00:00 (300—500 hours)
Is this possible??