Contents of Description field get lost if saved in preview mode

Steps to Reproduce:
1. Launch JIRA.
2. Create/update an issue and enter value in description field. Say
text

xxx

3. Click the "Preview" icon to see the value in preview mode.
4. Click "Create"/"Update".

Result:
1. The issue just get created with summary and data in description field is lost.
2. This is a critical issue as user is here loosing data if saved in preview mode.

Expected:
1. No loss of data

Additional Info:
Working fine on JAC