Validating input

Hi there,
is there a way to do client side validation vor min., max. values.
I have to check if a value entered is within a certain range e.g. 5-104.
How can these constraint be provided (dynamic and static?)
Help would be appreciated.

Best regards,

…and with the new version 2.2 (released January this year) the FIELD control provides for a validation rules editor. See attached schreenshot to see the rule the interval 5-104.