Request with SQL bb-code highlighting is shown in different way in Preview and after submitting

Steps to reproduce:

1. Open "New message/Compose" in PM
2. Select SQL code in the code drop-down menu
3. Enter following text SELECT * FROM users WHERE user_id = :user_id; instead of 'Insert your text here'
4. Press "Preview" button
5. Send a message to some User
6. Click on last message subject in Outbox folder

Actual result: SQL request has different style in Preview and in Outbox folder. Line numbering is absent

Expected result: SQL request has number of line in Preview and in Outbox folder
User receives this message without line numbering.