Workflow Validator doesn't show Error

Original Description:

If you add a workflow validator on the create issue.
Like to validate that a field concur with certain condition.
(IE: Number field that contain at least that quantity of numbers)
and if the client what fill the form doesn't concur with the condition, it will not show the error written in the validator, but will show a generic: Not able to create issue via this Service Desk

It should show the proper error like if creating this issue in Jira.

Thanks

Steps to Reproduce:

1. Install e.g. the JIRA Suite Utilities add-on;
2. Edit the workflow being used by the Service Desk;
3. Add the Date Expression Compare Validator to the Create Issue transition;
4. Select the "Due Date" field;
   • Condition ">="
   • Compare with '5d'
   • include time part: No
5. Try to create a request through the customer portal, but chose a Due Date < currentDate + 5d.

Expected Behavior:

The same error message that appears when creating the issue through the default create issue screen in JIRA should appear on the Customer Portal screen.

Actual Behavior:

This error is displayed

Workaround:

Use the Field help field in the Customer Portal to show a detailed description of what is being validated in each field.