Error message when user attempts to enter more characters in a field than its length

We have a requirement to display an error message when user attempts to enter more characters than its length in a field. For instance, there is a Description field with a length of 4,000 characters and we need to display an error message if user enters a text with more than 4,000 characters (may be copy & paste). Suggested error message: "Value too long for field 'Description' (maximum size 4,000).".

Currently in Siebel as per out-of-the-box, user is not able to enter more than 4,000 characters and no error message is displayed. In case of copy & paste, the text is always truncated.

We would like to know if it is possible to implement this validation using PM/PR files. Please kindly share your thoughts on how to implement this requirement.